ocaml / otherlibs / unix / unix.mli

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
(***********************************************************************)
(*                                                                     *)
(*                                OCaml                                *)
(*                                                                     *)
(*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         *)
(*                                                                     *)
(*  Copyright 1996 Institut National de Recherche en Informatique et   *)
(*  en Automatique.  All rights reserved.  This file is distributed    *)
(*  under the terms of the GNU Library General Public License, with    *)
(*  the special exception on linking described in file ../../LICENSE.  *)
(*                                                                     *)
(***********************************************************************)

(* $Id$ *)

(** Interface to the Unix system *)


(** {6 Error report} *)


type error =
    E2BIG               (** Argument list too long *)
  | EACCES              (** Permission denied *)
  | EAGAIN              (** Resource temporarily unavailable; try again *)
  | EBADF               (** Bad file descriptor *)
  | EBUSY               (** Resource unavailable *)
  | ECHILD              (** No child process *)
  | EDEADLK             (** Resource deadlock would occur *)
  | EDOM                (** Domain error for math functions, etc. *)
  | EEXIST              (** File exists *)
  | EFAULT              (** Bad address *)
  | EFBIG               (** File too large *)
  | EINTR               (** Function interrupted by signal *)
  | EINVAL              (** Invalid argument *)
  | EIO                 (** Hardware I/O error *)
  | EISDIR              (** Is a directory *)
  | EMFILE              (** Too many open files by the process *)
  | EMLINK              (** Too many links *)
  | ENAMETOOLONG        (** Filename too long *)
  | ENFILE              (** Too many open files in the system *)
  | ENODEV              (** No such device *)
  | ENOENT              (** No such file or directory *)
  | ENOEXEC             (** Not an executable file *)
  | ENOLCK              (** No locks available *)
  | ENOMEM              (** Not enough memory *)
  | ENOSPC              (** No space left on device *)
  | ENOSYS              (** Function not supported *)
  | ENOTDIR             (** Not a directory *)
  | ENOTEMPTY           (** Directory not empty *)
  | ENOTTY              (** Inappropriate I/O control operation *)
  | ENXIO               (** No such device or address *)
  | EPERM               (** Operation not permitted *)
  | EPIPE               (** Broken pipe *)
  | ERANGE              (** Result too large *)
  | EROFS               (** Read-only file system *)
  | ESPIPE              (** Invalid seek e.g. on a pipe *)
  | ESRCH               (** No such process *)
  | EXDEV               (** Invalid link *)
  | EWOULDBLOCK         (** Operation would block *)
  | EINPROGRESS         (** Operation now in progress *)
  | EALREADY            (** Operation already in progress *)
  | ENOTSOCK            (** Socket operation on non-socket *)
  | EDESTADDRREQ        (** Destination address required *)
  | EMSGSIZE            (** Message too long *)
  | EPROTOTYPE          (** Protocol wrong type for socket *)
  | ENOPROTOOPT         (** Protocol not available *)
  | EPROTONOSUPPORT     (** Protocol not supported *)
  | ESOCKTNOSUPPORT     (** Socket type not supported *)
  | EOPNOTSUPP          (** Operation not supported on socket *)
  | EPFNOSUPPORT        (** Protocol family not supported *)
  | EAFNOSUPPORT        (** Address family not supported by protocol family *)
  | EADDRINUSE          (** Address already in use *)
  | EADDRNOTAVAIL       (** Can't assign requested address *)
  | ENETDOWN            (** Network is down *)
  | ENETUNREACH         (** Network is unreachable *)
  | ENETRESET           (** Network dropped connection on reset *)
  | ECONNABORTED        (** Software caused connection abort *)
  | ECONNRESET          (** Connection reset by peer *)
  | ENOBUFS             (** No buffer space available *)
  | EISCONN             (** Socket is already connected *)
  | ENOTCONN            (** Socket is not connected *)
  | ESHUTDOWN           (** Can't send after socket shutdown *)
  | ETOOMANYREFS        (** Too many references: can't splice *)
  | ETIMEDOUT           (** Connection timed out *)
  | ECONNREFUSED        (** Connection refused *)
  | EHOSTDOWN           (** Host is down *)
  | EHOSTUNREACH        (** No route to host *)
  | ELOOP               (** Too many levels of symbolic links *)
  | EOVERFLOW           (** File size or position not representable *)

  | EUNKNOWNERR of int  (** Unknown error *)
(** The type of error codes.
   Errors defined in the POSIX standard
   and additional errors from UNIX98 and BSD.
   All other errors are mapped to EUNKNOWNERR.
*)


exception Unix_error of error * string * string
(** Raised by the system calls below when an error is encountered.
   The first component is the error code; the second component
   is the function name; the third component is the string parameter
   to the function, if it has one, or the empty string otherwise. *)

val error_message : error -> string
(** Return a string describing the given error code. *)

val handle_unix_error : ('a -> 'b) -> 'a -> 'b
(** [handle_unix_error f x] applies [f] to [x] and returns the result.
   If the exception [Unix_error] is raised, it prints a message
   describing the error and exits with code 2. *)


(** {6 Access to the process environment} *)


val environment : unit -> string array
(** Return the process environment, as an array of strings
    with the format ``variable=value''. *)

val getenv : string -> string
(** Return the value associated to a variable in the process
   environment. Raise [Not_found] if the variable is unbound.
   (This function is identical to {!Sys.getenv}.) *)

val putenv : string -> string -> unit
(** [Unix.putenv name value] sets the value associated to a
   variable in the process environment.
   [name] is the name of the environment variable,
   and [value] its new associated value. *)


(** {6 Process handling} *)


type process_status =
    WEXITED of int
        (** The process terminated normally by [exit];
           the argument is the return code. *)
  | WSIGNALED of int
        (** The process was killed by a signal;
           the argument is the signal number. *)
  | WSTOPPED of int
        (** The process was stopped by a signal; the argument is the
           signal number. *)
(** The termination status of a process.  See module {!Sys} for the
    definitions of the standard signal numbers.  Note that they are
    not the numbers used by the OS. *)


type wait_flag =
    WNOHANG (** do not block if no child has
               died yet, but immediately return with a pid equal to 0.*)
  | WUNTRACED (** report also the children that receive stop signals. *)
(** Flags for {!Unix.waitpid}. *)

val execv : string -> string array -> 'a
(** [execv prog args] execute the program in file [prog], with
   the arguments [args], and the current process environment.
   These [execv*] functions never return: on success, the current
   program is replaced by the new one;
   on failure, a {!Unix.Unix_error} exception is raised. *)

val execve : string -> string array -> string array -> 'a
(** Same as {!Unix.execv}, except that the third argument provides the
   environment to the program executed. *)

val execvp : string -> string array -> 'a
(** Same as {!Unix.execv}, except that
   the program is searched in the path. *)

val execvpe : string -> string array -> string array -> 'a
(** Same as {!Unix.execve}, except that
   the program is searched in the path. *)

val fork : unit -> int
(** Fork a new process. The returned integer is 0 for the child
   process, the pid of the child process for the parent process. *)

val wait : unit -> int * process_status
(** Wait until one of the children processes die, and return its pid
   and termination status. *)

val waitpid : wait_flag list -> int -> int * process_status
(** Same as {!Unix.wait}, but waits for the child process whose pid is given.
   A pid of [-1] means wait for any child.
   A pid of [0] means wait for any child in the same process group
   as the current process.
   Negative pid arguments represent process groups.
   The list of options indicates whether [waitpid] should return
   immediately without waiting, and whether it should report stopped
   children. *)

val system : string -> process_status
(** Execute the given command, wait until it terminates, and return
   its termination status. The string is interpreted by the shell
   [/bin/sh] and therefore can contain redirections, quotes, variables,
   etc. The result [WEXITED 127] indicates that the shell couldn't
   be executed. *)

val getpid : unit -> int
(** Return the pid of the process. *)

val getppid : unit -> int
(** Return the pid of the parent process. *)

val nice : int -> int
(** Change the process priority. The integer argument is added to the
   ``nice'' value. (Higher values of the ``nice'' value mean
   lower priorities.) Return the new nice value. *)


(** {6 Basic file input/output} *)


type file_descr
(** The abstract type of file descriptors. *)

val stdin : file_descr
(** File descriptor for standard input.*)

val stdout : file_descr
(** File descriptor for standard output.*)

val stderr : file_descr
(** File descriptor for standard error. *)

type open_flag =
    O_RDONLY                    (** Open for reading *)
  | O_WRONLY                    (** Open for writing *)
  | O_RDWR                      (** Open for reading and writing *)
  | O_NONBLOCK                  (** Open in non-blocking mode *)
  | O_APPEND                    (** Open for append *)
  | O_CREAT                     (** Create if nonexistent *)
  | O_TRUNC                     (** Truncate to 0 length if existing *)
  | O_EXCL                      (** Fail if existing *)
  | O_NOCTTY                    (** Don't make this dev a controlling tty *)
  | O_DSYNC                     (** Writes complete as `Synchronised I/O data
                                   integrity completion' *)
  | O_SYNC                      (** Writes complete as `Synchronised I/O file
                                   integrity completion' *)
  | O_RSYNC                     (** Reads complete as writes (depending on
                                   O_SYNC/O_DSYNC) *)
  | O_SHARE_DELETE              (** Windows only: allow the file to be deleted
                                   while still open *)
(** The flags to {!Unix.openfile}. *)


type file_perm = int
(** The type of file access rights, e.g. [0o640] is read and write for user,
    read for group, none for others *)

val openfile : string -> open_flag list -> file_perm -> file_descr
(** Open the named file with the given flags. Third argument is
   the permissions to give to the file if it is created. Return
   a file descriptor on the named file. *)

val close : file_descr -> unit
(** Close a file descriptor. *)

val read : file_descr -> string -> int -> int -> int
(** [read fd buff ofs len] reads [len] characters from descriptor
   [fd], storing them in string [buff], starting at position [ofs]
   in string [buff]. Return the number of characters actually read. *)

val write : file_descr -> string -> int -> int -> int
(** [write fd buff ofs len] writes [len] characters to descriptor
   [fd], taking them from string [buff], starting at position [ofs]
   in string [buff]. Return the number of characters actually
   written.  [write] repeats the writing operation until all characters
   have been written or an error occurs.  *)

val single_write : file_descr -> string -> int -> int -> int
(** Same as [write], but attempts to write only once.
   Thus, if an error occurs, [single_write] guarantees that no data
   has been written. *)

(** {6 Interfacing with the standard input/output library} *)



val in_channel_of_descr : file_descr -> in_channel
(** Create an input channel reading from the given descriptor.
   The channel is initially in binary mode; use
   [set_binary_mode_in ic false] if text mode is desired. *)

val out_channel_of_descr : file_descr -> out_channel
(** Create an output channel writing on the given descriptor.
   The channel is initially in binary mode; use
   [set_binary_mode_out oc false] if text mode is desired. *)

val descr_of_in_channel : in_channel -> file_descr
(** Return the descriptor corresponding to an input channel. *)

val descr_of_out_channel : out_channel -> file_descr
(** Return the descriptor corresponding to an output channel. *)


(** {6 Seeking and truncating} *)


type seek_command =
    SEEK_SET (** indicates positions relative to the beginning of the file *)
  | SEEK_CUR (** indicates positions relative to the current position *)
  | SEEK_END (** indicates positions relative to the end of the file *)
(** Positioning modes for {!Unix.lseek}. *)


val lseek : file_descr -> int -> seek_command -> int
(** Set the current position for a file descriptor *)

val truncate : string -> int -> unit
(** Truncates the named file to the given size. *)

val ftruncate : file_descr -> int -> unit
(** Truncates the file corresponding to the given descriptor
   to the given size. *)


(** {6 File status} *)


type file_kind =
    S_REG                       (** Regular file *)
  | S_DIR                       (** Directory *)
  | S_CHR                       (** Character device *)
  | S_BLK                       (** Block device *)
  | S_LNK                       (** Symbolic link *)
  | S_FIFO                      (** Named pipe *)
  | S_SOCK                      (** Socket *)

type stats =
  { st_dev : int;               (** Device number *)
    st_ino : int;               (** Inode number *)
    st_kind : file_kind;        (** Kind of the file *)
    st_perm : file_perm;        (** Access rights *)
    st_nlink : int;             (** Number of links *)
    st_uid : int;               (** User id of the owner *)
    st_gid : int;               (** Group ID of the file's group *)
    st_rdev : int;              (** Device minor number *)
    st_size : int;              (** Size in bytes *)
    st_atime : float;           (** Last access time *)
    st_mtime : float;           (** Last modification time *)
    st_ctime : float;           (** Last status change time *)
  }
(** The information returned by the {!Unix.stat} calls. *)

val stat : string -> stats
(** Return the information for the named file. *)

val lstat : string -> stats
(** Same as {!Unix.stat}, but in case the file is a symbolic link,
   return the information for the link itself. *)

val fstat : file_descr -> stats
(** Return the information for the file associated with the given
   descriptor. *)

val isatty : file_descr -> bool
(** Return [true] if the given file descriptor refers to a terminal or
   console window, [false] otherwise. *)

(** {6 File operations on large files} *)

module LargeFile :
  sig
    val lseek : file_descr -> int64 -> seek_command -> int64
    val truncate : string -> int64 -> unit
    val ftruncate : file_descr -> int64 -> unit
    type stats =
      { st_dev : int;               (** Device number *)
        st_ino : int;               (** Inode number *)
        st_kind : file_kind;        (** Kind of the file *)
        st_perm : file_perm;        (** Access rights *)
        st_nlink : int;             (** Number of links *)
        st_uid : int;               (** User id of the owner *)
        st_gid : int;               (** Group ID of the file's group *)
        st_rdev : int;              (** Device minor number *)
        st_size : int64;            (** Size in bytes *)
        st_atime : float;           (** Last access time *)
        st_mtime : float;           (** Last modification time *)
        st_ctime : float;           (** Last status change time *)
      }
    val stat : string -> stats
    val lstat : string -> stats
    val fstat : file_descr -> stats
  end
(** File operations on large files.
  This sub-module provides 64-bit variants of the functions
  {!Unix.lseek} (for positioning a file descriptor),
  {!Unix.truncate} and {!Unix.ftruncate} (for changing the size of a file),
  and {!Unix.stat}, {!Unix.lstat} and {!Unix.fstat} (for obtaining
  information on files).  These alternate functions represent
  positions and sizes by 64-bit integers (type [int64]) instead of
  regular integers (type [int]), thus allowing operating on files
  whose sizes are greater than [max_int]. *)


(** {6 Operations on file names} *)


val unlink : string -> unit
(** Removes the named file *)

val rename : string -> string -> unit
(** [rename old new] changes the name of a file from [old] to [new]. *)

val link : string -> string -> unit
(** [link source dest] creates a hard link named [dest] to the file
   named [source]. *)


(** {6 File permissions and ownership} *)


type access_permission =
    R_OK                        (** Read permission *)
  | W_OK                        (** Write permission *)
  | X_OK                        (** Execution permission *)
  | F_OK                        (** File exists *)
(** Flags for the {!Unix.access} call. *)


val chmod : string -> file_perm -> unit
(** Change the permissions of the named file. *)

val fchmod : file_descr -> file_perm -> unit
(** Change the permissions of an opened file. *)

val chown : string -> int -> int -> unit
(** Change the owner uid and owner gid of the named file. *)

val fchown : file_descr -> int -> int -> unit
(** Change the owner uid and owner gid of an opened file. *)

val umask : int -> int
(** Set the process's file mode creation mask, and return the previous
    mask. *)

val access : string -> access_permission list -> unit
(** Check that the process has the given permissions over the named
   file. Raise [Unix_error] otherwise. *)


(** {6 Operations on file descriptors} *)


val dup : file_descr -> file_descr
(** Return a new file descriptor referencing the same file as
   the given descriptor. *)

val dup2 : file_descr -> file_descr -> unit
(** [dup2 fd1 fd2] duplicates [fd1] to [fd2], closing [fd2] if already
   opened. *)

val set_nonblock : file_descr -> unit
(** Set the ``non-blocking'' flag on the given descriptor.
   When the non-blocking flag is set, reading on a descriptor
   on which there is temporarily no data available raises the
   [EAGAIN] or [EWOULDBLOCK] error instead of blocking;
   writing on a descriptor on which there is temporarily no room
   for writing also raises [EAGAIN] or [EWOULDBLOCK]. *)

val clear_nonblock : file_descr -> unit
(** Clear the ``non-blocking'' flag on the given descriptor.
   See {!Unix.set_nonblock}.*)

val set_close_on_exec : file_descr -> unit
(** Set the ``close-on-exec'' flag on the given descriptor.
   A descriptor with the close-on-exec flag is automatically
   closed when the current process starts another program with
   one of the [exec] functions. *)

val clear_close_on_exec : file_descr -> unit
(** Clear the ``close-on-exec'' flag on the given descriptor.
   See {!Unix.set_close_on_exec}.*)


(** {6 Directories} *)


val mkdir : string -> file_perm -> unit
(** Create a directory with the given permissions. *)

val rmdir : string -> unit
(** Remove an empty directory. *)

val chdir : string -> unit
(** Change the process working directory. *)

val getcwd : unit -> string
(** Return the name of the current working directory. *)

val chroot : string -> unit
(** Change the process root directory. *)

type dir_handle
(** The type of descriptors over opened directories. *)

val opendir : string -> dir_handle
(** Open a descriptor on a directory *)

val readdir : dir_handle -> string
(** Return the next entry in a directory.
   @raise End_of_file when the end of the directory has been reached. *)

val rewinddir : dir_handle -> unit
(** Reposition the descriptor to the beginning of the directory *)

val closedir : dir_handle -> unit
(** Close a directory descriptor. *)



(** {6 Pipes and redirections} *)


val pipe : unit -> file_descr * file_descr
(** Create a pipe. The first component of the result is opened
   for reading, that's the exit to the pipe. The second component is
   opened for writing, that's the entrance to the pipe. *)

val mkfifo : string -> file_perm -> unit
(** Create a named pipe with the given permissions. *)


(** {6 High-level process and redirection management} *)


val create_process :
  string -> string array -> file_descr -> file_descr -> file_descr -> int
(** [create_process prog args new_stdin new_stdout new_stderr]
   forks a new process that executes the program
   in file [prog], with arguments [args]. The pid of the new
   process is returned immediately; the new process executes
   concurrently with the current process.
   The standard input and outputs of the new process are connected
   to the descriptors [new_stdin], [new_stdout] and [new_stderr].
   Passing e.g. [stdout] for [new_stdout] prevents the redirection
   and causes the new process to have the same standard output
   as the current process.
   The executable file [prog] is searched in the path.
   The new process has the same environment as the current process. *)

val create_process_env :
  string -> string array -> string array -> file_descr -> file_descr ->
    file_descr -> int
(** [create_process_env prog args env new_stdin new_stdout new_stderr]
   works as {!Unix.create_process}, except that the extra argument
   [env] specifies the environment passed to the program. *)


val open_process_in : string -> in_channel
(** High-level pipe and process management. This function
   runs the given command in parallel with the program.
   The standard output of the command is redirected to a pipe,
   which can be read via the returned input channel.
   The command is interpreted by the shell [/bin/sh] (cf. [system]). *)

val open_process_out : string -> out_channel
(** Same as {!Unix.open_process_in}, but redirect the standard input of
   the command to a pipe.  Data written to the returned output channel
   is sent to the standard input of the command.
   Warning: writes on output channels are buffered, hence be careful
   to call {!Pervasives.flush} at the right times to ensure
   correct synchronization. *)

val open_process : string -> in_channel * out_channel
(** Same as {!Unix.open_process_out}, but redirects both the standard input
   and standard output of the command to pipes connected to the two
   returned channels.  The input channel is connected to the output
   of the command, and the output channel to the input of the command. *)

val open_process_full :
  string -> string array -> in_channel * out_channel * in_channel
(** Similar to {!Unix.open_process}, but the second argument specifies
   the environment passed to the command.  The result is a triple
   of channels connected respectively to the standard output, standard input,
   and standard error of the command. *)

val close_process_in : in_channel -> process_status
(** Close channels opened by {!Unix.open_process_in},
   wait for the associated command to terminate,
   and return its termination status. *)

val close_process_out : out_channel -> process_status
(** Close channels opened by {!Unix.open_process_out},
   wait for the associated command to terminate,
   and return its termination status. *)

val close_process : in_channel * out_channel -> process_status
(** Close channels opened by {!Unix.open_process},
   wait for the associated command to terminate,
   and return its termination status. *)

val close_process_full :
  in_channel * out_channel * in_channel -> process_status
(** Close channels opened by {!Unix.open_process_full},
   wait for the associated command to terminate,
   and return its termination status. *)


(** {6 Symbolic links} *)


val symlink : string -> string -> unit
(** [symlink source dest] creates the file [dest] as a symbolic link
   to the file [source]. *)

val readlink : string -> string
(** Read the contents of a link. *)


(** {6 Polling} *)


val select :
  file_descr list -> file_descr list -> file_descr list -> float ->
    file_descr list * file_descr list * file_descr list
(** Wait until some input/output operations become possible on
   some channels. The three list arguments are, respectively, a set
   of descriptors to check for reading (first argument), for writing
   (second argument), or for exceptional conditions (third argument).
   The fourth argument is the maximal timeout, in seconds; a
   negative fourth argument means no timeout (unbounded wait).
   The result is composed of three sets of descriptors: those ready
   for reading (first component), ready for writing (second component),
   and over which an exceptional condition is pending (third
   component). *)

(** {6 Locking} *)


type lock_command =
    F_ULOCK       (** Unlock a region *)
  | F_LOCK        (** Lock a region for writing, and block if already locked *)
  | F_TLOCK       (** Lock a region for writing, or fail if already locked *)
  | F_TEST        (** Test a region for other process locks *)
  | F_RLOCK       (** Lock a region for reading, and block if already locked *)
  | F_TRLOCK      (** Lock a region for reading, or fail if already locked *)
(** Commands for {!Unix.lockf}. *)

val lockf : file_descr -> lock_command -> int -> unit
(** [lockf fd cmd size] puts a lock on a region of the file opened
   as [fd]. The region starts at the current read/write position for
   [fd] (as set by {!Unix.lseek}), and extends [size] bytes forward if
   [size] is positive, [size] bytes backwards if [size] is negative,
   or to the end of the file if [size] is zero.
   A write lock prevents any other
   process from acquiring a read or write lock on the region.
   A read lock prevents any other
   process from acquiring a write lock on the region, but lets
   other processes acquire read locks on it.

   The [F_LOCK] and [F_TLOCK] commands attempts to put a write lock
   on the specified region.
   The [F_RLOCK] and [F_TRLOCK] commands attempts to put a read lock
   on the specified region.
   If one or several locks put by another process prevent the current process
   from acquiring the lock, [F_LOCK] and [F_RLOCK] block until these locks
   are removed, while [F_TLOCK] and [F_TRLOCK] fail immediately with an
   exception.
   The [F_ULOCK] removes whatever locks the current process has on
   the specified region.
   Finally, the [F_TEST] command tests whether a write lock can be
   acquired on the specified region, without actually putting a lock.
   It returns immediately if successful, or fails otherwise. *)


(** {6 Signals}
   Note: installation of signal handlers is performed via
   the functions {!Sys.signal} and {!Sys.set_signal}.
*)

val kill : int -> int -> unit
(** [kill pid sig] sends signal number [sig] to the process
   with id [pid]. *)

type sigprocmask_command =
    SIG_SETMASK
  | SIG_BLOCK
  | SIG_UNBLOCK

val sigprocmask : sigprocmask_command -> int list -> int list
(** [sigprocmask cmd sigs] changes the set of blocked signals.
   If [cmd] is [SIG_SETMASK], blocked signals are set to those in
   the list [sigs].
   If [cmd] is [SIG_BLOCK], the signals in [sigs] are added to
   the set of blocked signals.
   If [cmd] is [SIG_UNBLOCK], the signals in [sigs] are removed
   from the set of blocked signals.
   [sigprocmask] returns the set of previously blocked signals. *)

val sigpending : unit -> int list
(** Return the set of blocked signals that are currently pending. *)

val sigsuspend : int list -> unit
(** [sigsuspend sigs] atomically sets the blocked signals to [sigs]
   and waits for a non-ignored, non-blocked signal to be delivered.
   On return, the blocked signals are reset to their initial value. *)

val pause : unit -> unit
(** Wait until a non-ignored, non-blocked signal is delivered. *)


(** {6 Time functions} *)


type process_times =
  { tms_utime : float;  (** User time for the process *)
    tms_stime : float;  (** System time for the process *)
    tms_cutime : float; (** User time for the children processes *)
    tms_cstime : float; (** System time for the children processes *)
  }
(** The execution times (CPU times) of a process. *)

type tm =
  { tm_sec : int;               (** Seconds 0..60 *)
    tm_min : int;               (** Minutes 0..59 *)
    tm_hour : int;              (** Hours 0..23 *)
    tm_mday : int;              (** Day of month 1..31 *)
    tm_mon : int;               (** Month of year 0..11 *)
    tm_year : int;              (** Year - 1900 *)
    tm_wday : int;              (** Day of week (Sunday is 0) *)
    tm_yday : int;              (** Day of year 0..365 *)
    tm_isdst : bool;            (** Daylight time savings in effect *)
  }
(** The type representing wallclock time and calendar date. *)


val time : unit -> float
(** Return the current time since 00:00:00 GMT, Jan. 1, 1970,
   in seconds. *)

val gettimeofday : unit -> float
(** Same as {!Unix.time}, but with resolution better than 1 second. *)

val gmtime : float -> tm
(** Convert a time in seconds, as returned by {!Unix.time}, into a date and
   a time. Assumes UTC (Coordinated Universal Time), also known as GMT. *)

val localtime : float -> tm
(** Convert a time in seconds, as returned by {!Unix.time}, into a date and
   a time. Assumes the local time zone. *)

val mktime : tm -> float * tm
(** Convert a date and time, specified by the [tm] argument, into
   a time in seconds, as returned by {!Unix.time}.  The [tm_isdst],
   [tm_wday] and [tm_yday] fields of [tm] are ignored.  Also return a
   normalized copy of the given [tm] record, with the [tm_wday],
   [tm_yday], and [tm_isdst] fields recomputed from the other fields,
   and the other fields normalized (so that, e.g., 40 October is
   changed into 9 November).  The [tm] argument is interpreted in the
   local time zone. *)

val alarm : int -> int
(** Schedule a [SIGALRM] signal after the given number of seconds. *)

val sleep : int -> unit
(** Stop execution for the given number of seconds. *)

val times : unit -> process_times
(** Return the execution times of the process. *)

val utimes : string -> float -> float -> unit
(** Set the last access time (second arg) and last modification time
   (third arg) for a file. Times are expressed in seconds from
   00:00:00 GMT, Jan. 1, 1970.  A time of [0.0] is interpreted as the
   current time. *)

type interval_timer =
    ITIMER_REAL
      (** decrements in real time, and sends the signal [SIGALRM] when
         expired.*)
  | ITIMER_VIRTUAL
      (** decrements in process virtual time, and sends [SIGVTALRM]
          when expired. *)
  | ITIMER_PROF
      (** (for profiling) decrements both when the process
         is running and when the system is running on behalf of the
         process; it sends [SIGPROF] when expired. *)
(** The three kinds of interval timers. *)

type interval_timer_status =
  { it_interval : float;         (** Period *)
    it_value : float;            (** Current value of the timer *)
  }
(** The type describing the status of an interval timer *)

val getitimer : interval_timer -> interval_timer_status
(** Return the current status of the given interval timer. *)

val setitimer :
  interval_timer -> interval_timer_status -> interval_timer_status
(** [setitimer t s] sets the interval timer [t] and returns
   its previous status. The [s] argument is interpreted as follows:
   [s.it_value], if nonzero, is the time to the next timer expiration;
   [s.it_interval], if nonzero, specifies a value to
   be used in reloading it_value when the timer expires.
   Setting [s.it_value] to zero disable the timer.
   Setting [s.it_interval] to zero causes the timer to be disabled
   after its next expiration. *)


(** {6 User id, group id} *)


val getuid : unit -> int
(** Return the user id of the user executing the process. *)

val geteuid : unit -> int
(** Return the effective user id under which the process runs. *)

val setuid : int -> unit
(** Set the real user id and effective user id for the process. *)

val getgid : unit -> int
(** Return the group id of the user executing the process. *)

val getegid : unit -> int
(** Return the effective group id under which the process runs. *)

val setgid : int -> unit
(** Set the real group id and effective group id for the process. *)

val getgroups : unit -> int array
(** Return the list of groups to which the user executing the process
   belongs. *)

val setgroups : int array -> unit
  (** [setgroups groups] sets the supplementary group IDs for the
      calling process. Appropriate privileges are required. *)

val initgroups : string -> int -> unit
  (** [initgroups user group] initializes the group access list by
      reading the group database /etc/group and using all groups of
      which [user] is a member. The additional group [group] is also
      added to the list. *)

type passwd_entry =
  { pw_name : string;
    pw_passwd : string;
    pw_uid : int;
    pw_gid : int;
    pw_gecos : string;
    pw_dir : string;
    pw_shell : string
  }
(** Structure of entries in the [passwd] database. *)

type group_entry =
  { gr_name : string;
    gr_passwd : string;
    gr_gid : int;
    gr_mem : string array
  }
(** Structure of entries in the [groups] database. *)

val getlogin : unit -> string
(** Return the login name of the user executing the process. *)

val getpwnam : string -> passwd_entry
(** Find an entry in [passwd] with the given name, or raise
   [Not_found]. *)

val getgrnam : string -> group_entry
(** Find an entry in [group] with the given name, or raise
   [Not_found]. *)

val getpwuid : int -> passwd_entry
(** Find an entry in [passwd] with the given user id, or raise
   [Not_found]. *)

val getgrgid : int -> group_entry
(** Find an entry in [group] with the given group id, or raise
   [Not_found]. *)


(** {6 Internet addresses} *)


type inet_addr
(** The abstract type of Internet addresses. *)

val inet_addr_of_string : string -> inet_addr
(** Conversion from the printable representation of an Internet
    address to its internal representation.  The argument string
    consists of 4 numbers separated by periods ([XXX.YYY.ZZZ.TTT])
    for IPv4 addresses, and up to 8 numbers separated by colons
    for IPv6 addresses.  Raise [Failure] when given a string that
    does not match these formats. *)

val string_of_inet_addr : inet_addr -> string
(** Return the printable representation of the given Internet address.
    See {!Unix.inet_addr_of_string} for a description of the
    printable representation. *)

val inet_addr_any : inet_addr
(** A special IPv4 address, for use only with [bind], representing
   all the Internet addresses that the host machine possesses. *)

val inet_addr_loopback : inet_addr
(** A special IPv4 address representing the host machine ([127.0.0.1]). *)

val inet6_addr_any : inet_addr
(** A special IPv6 address, for use only with [bind], representing
   all the Internet addresses that the host machine possesses. *)

val inet6_addr_loopback : inet_addr
(** A special IPv6 address representing the host machine ([::1]). *)


(** {6 Sockets} *)


type socket_domain =
    PF_UNIX                     (** Unix domain *)
  | PF_INET                     (** Internet domain (IPv4) *)
  | PF_INET6                    (** Internet domain (IPv6) *)
(** The type of socket domains.  Not all platforms support
    IPv6 sockets (type [PF_INET6]). *)

type socket_type =
    SOCK_STREAM                 (** Stream socket *)
  | SOCK_DGRAM                  (** Datagram socket *)
  | SOCK_RAW                    (** Raw socket *)
  | SOCK_SEQPACKET              (** Sequenced packets socket *)
(** The type of socket kinds, specifying the semantics of
   communications. *)

type sockaddr =
    ADDR_UNIX of string
  | ADDR_INET of inet_addr * int
(** The type of socket addresses. [ADDR_UNIX name] is a socket
   address in the Unix domain; [name] is a file name in the file
   system. [ADDR_INET(addr,port)] is a socket address in the Internet
   domain; [addr] is the Internet address of the machine, and
   [port] is the port number. *)

val socket : socket_domain -> socket_type -> int -> file_descr
(** Create a new socket in the given domain, and with the
   given kind. The third argument is the protocol type; 0 selects
   the default protocol for that kind of sockets. *)

val domain_of_sockaddr: sockaddr -> socket_domain
(** Return the socket domain adequate for the given socket address. *)

val socketpair :
  socket_domain -> socket_type -> int -> file_descr * file_descr
(** Create a pair of unnamed sockets, connected together. *)

val accept : file_descr -> file_descr * sockaddr
(** Accept connections on the given socket. The returned descriptor
   is a socket connected to the client; the returned address is
   the address of the connecting client. *)

val bind : file_descr -> sockaddr -> unit
(** Bind a socket to an address. *)

val connect : file_descr -> sockaddr -> unit
(** Connect a socket to an address. *)

val listen : file_descr -> int -> unit
(** Set up a socket for receiving connection requests. The integer
   argument is the maximal number of pending requests. *)

type shutdown_command =
    SHUTDOWN_RECEIVE            (** Close for receiving *)
  | SHUTDOWN_SEND               (** Close for sending *)
  | SHUTDOWN_ALL                (** Close both *)
(** The type of commands for [shutdown]. *)


val shutdown : file_descr -> shutdown_command -> unit
(** Shutdown a socket connection. [SHUTDOWN_SEND] as second argument
   causes reads on the other end of the connection to return
   an end-of-file condition.
   [SHUTDOWN_RECEIVE] causes writes on the other end of the connection
   to return a closed pipe condition ([SIGPIPE] signal). *)

val getsockname : file_descr -> sockaddr
(** Return the address of the given socket. *)

val getpeername : file_descr -> sockaddr
(** Return the address of the host connected to the given socket. *)

type msg_flag =
    MSG_OOB
  | MSG_DONTROUTE
  | MSG_PEEK
(** The flags for {!Unix.recv},  {!Unix.recvfrom},
   {!Unix.send} and {!Unix.sendto}. *)

val recv : file_descr -> string -> int -> int -> msg_flag list -> int
(** Receive data from a connected socket. *)

val recvfrom :
  file_descr -> string -> int -> int -> msg_flag list -> int * sockaddr
(** Receive data from an unconnected socket. *)

val send : file_descr -> string -> int -> int -> msg_flag list -> int
(** Send data over a connected socket. *)

val sendto :
  file_descr -> string -> int -> int -> msg_flag list -> sockaddr -> int
(** Send data over an unconnected socket. *)



(** {6 Socket options} *)


type socket_bool_option =
    SO_DEBUG       (** Record debugging information *)
  | SO_BROADCAST   (** Permit sending of broadcast messages *)
  | SO_REUSEADDR   (** Allow reuse of local addresses for bind *)
  | SO_KEEPALIVE   (** Keep connection active *)
  | SO_DONTROUTE   (** Bypass the standard routing algorithms *)
  | SO_OOBINLINE   (** Leave out-of-band data in line *)
  | SO_ACCEPTCONN  (** Report whether socket listening is enabled *)
  | TCP_NODELAY    (** Control the Nagle algorithm for TCP sockets *)
  | IPV6_ONLY      (** Forbid binding an IPv6 socket to an IPv4 address *)
(** The socket options that can be consulted with {!Unix.getsockopt}
   and modified with {!Unix.setsockopt}.  These options have a boolean
   ([true]/[false]) value. *)

type socket_int_option =
    SO_SNDBUF      (** Size of send buffer *)
  | SO_RCVBUF      (** Size of received buffer *)
  | SO_ERROR       (** Deprecated.  Use {!Unix.getsockopt_error} instead. *)
  | SO_TYPE        (** Report the socket type *)
  | SO_RCVLOWAT    (** Minimum number of bytes to process for input operations*)
  | SO_SNDLOWAT    (** Minimum number of bytes to process for output
                       operations *)
(** The socket options that can be consulted with {!Unix.getsockopt_int}
   and modified with {!Unix.setsockopt_int}.  These options have an
   integer value. *)

type socket_optint_option =
  SO_LINGER      (** Whether to linger on closed connections
                    that have data present, and for how long
                    (in seconds) *)
(** The socket options that can be consulted with {!Unix.getsockopt_optint}
   and modified with {!Unix.setsockopt_optint}.  These options have a
   value of type [int option], with [None] meaning ``disabled''. *)

type socket_float_option =
    SO_RCVTIMEO    (** Timeout for input operations *)
  | SO_SNDTIMEO    (** Timeout for output operations *)
(** The socket options that can be consulted with {!Unix.getsockopt_float}
   and modified with {!Unix.setsockopt_float}.  These options have a
   floating-point value representing a time in seconds.
   The value 0 means infinite timeout. *)

val getsockopt : file_descr -> socket_bool_option -> bool
(** Return the current status of a boolean-valued option
   in the given socket. *)

val setsockopt : file_descr -> socket_bool_option -> bool -> unit
(** Set or clear a boolean-valued option in the given socket. *)

val getsockopt_int : file_descr -> socket_int_option -> int
(** Same as {!Unix.getsockopt} for an integer-valued socket option. *)

val setsockopt_int : file_descr -> socket_int_option -> int -> unit
(** Same as {!Unix.setsockopt} for an integer-valued socket option. *)

val getsockopt_optint : file_descr -> socket_optint_option -> int option
(** Same as {!Unix.getsockopt} for a socket option whose value is an
   [int option]. *)

val setsockopt_optint :
      file_descr -> socket_optint_option -> int option -> unit
(** Same as {!Unix.setsockopt} for a socket option whose value is an
   [int option]. *)

val getsockopt_float : file_descr -> socket_float_option -> float
(** Same as {!Unix.getsockopt} for a socket option whose value is a
   floating-point number. *)

val setsockopt_float : file_descr -> socket_float_option -> float -> unit
(** Same as {!Unix.setsockopt} for a socket option whose value is a
   floating-point number. *)

val getsockopt_error : file_descr -> error option
(** Return the error condition associated with the given socket,
    and clear it. *)

(** {6 High-level network connection functions} *)


val open_connection : sockaddr -> in_channel * out_channel
(** Connect to a server at the given address.
   Return a pair of buffered channels connected to the server.
   Remember to call {!Pervasives.flush} on the output channel at the right
   times to ensure correct synchronization. *)

val shutdown_connection : in_channel -> unit
(** ``Shut down'' a connection established with {!Unix.open_connection};
   that is, transmit an end-of-file condition to the server reading
   on the other side of the connection. *)

val establish_server : (in_channel -> out_channel -> unit) -> sockaddr -> unit
(** Establish a server on the given address.
   The function given as first argument is called for each connection
   with two buffered channels connected to the client. A new process
   is created for each connection. The function {!Unix.establish_server}
   never returns normally. *)


(** {6 Host and protocol databases} *)


type host_entry =
  { h_name : string;
    h_aliases : string array;
    h_addrtype : socket_domain;
    h_addr_list : inet_addr array
  }
(** Structure of entries in the [hosts] database. *)

type protocol_entry =
  { p_name : string;
    p_aliases : string array;
    p_proto : int
  }
(** Structure of entries in the [protocols] database. *)

type service_entry =
  { s_name : string;
    s_aliases : string array;
    s_port : int;
    s_proto : string
  }
(** Structure of entries in the [services] database. *)

val gethostname : unit -> string
(** Return the name of the local host. *)

val gethostbyname : string -> host_entry
(** Find an entry in [hosts] with the given name, or raise
   [Not_found]. *)

val gethostbyaddr : inet_addr -> host_entry
(** Find an entry in [hosts] with the given address, or raise
   [Not_found]. *)

val getprotobyname : string -> protocol_entry
(** Find an entry in [protocols] with the given name, or raise
   [Not_found]. *)

val getprotobynumber : int -> protocol_entry
(** Find an entry in [protocols] with the given protocol number,
   or raise [Not_found]. *)

val getservbyname : string -> string -> service_entry
(** Find an entry in [services] with the given name, or raise
   [Not_found]. *)

val getservbyport : int -> string -> service_entry
(** Find an entry in [services] with the given service number,
   or raise [Not_found]. *)

type addr_info =
  { ai_family : socket_domain;          (** Socket domain *)
    ai_socktype : socket_type;          (** Socket type *)
    ai_protocol : int;                  (** Socket protocol number *)
    ai_addr : sockaddr;                 (** Address *)
    ai_canonname : string               (** Canonical host name  *)
  }
(** Address information returned by {!Unix.getaddrinfo}. *)

type getaddrinfo_option =
    AI_FAMILY of socket_domain          (** Impose the given socket domain *)
  | AI_SOCKTYPE of socket_type          (** Impose the given socket type *)
  | AI_PROTOCOL of int                  (** Impose the given protocol  *)
  | AI_NUMERICHOST                      (** Do not call name resolver,
                                            expect numeric IP address *)
  | AI_CANONNAME                        (** Fill the [ai_canonname] field
                                            of the result *)
  | AI_PASSIVE                          (** Set address to ``any'' address
                                            for use with {!Unix.bind} *)
(** Options to {!Unix.getaddrinfo}. *)

val getaddrinfo:
  string -> string -> getaddrinfo_option list -> addr_info list
(** [getaddrinfo host service opts] returns a list of {!Unix.addr_info}
    records describing socket parameters and addresses suitable for
    communicating with the given host and service.  The empty list is
    returned if the host or service names are unknown, or the constraints
    expressed in [opts] cannot be satisfied.

    [host] is either a host name or the string representation of an IP
    address.  [host] can be given as the empty string; in this case,
    the ``any'' address or the ``loopback'' address are used,
    depending whether [opts] contains [AI_PASSIVE].
    [service] is either a service name or the string representation of
    a port number.  [service] can be given as the empty string;
    in this case, the port field of the returned addresses is set to 0.
    [opts] is a possibly empty list of options that allows the caller
    to force a particular socket domain (e.g. IPv6 only or IPv4 only)
    or a particular socket type (e.g. TCP only or UDP only). *)

type name_info =
  { ni_hostname : string;               (** Name or IP address of host *)
    ni_service : string }               (** Name of service or port number *)
(** Host and service information returned by {!Unix.getnameinfo}. *)

type getnameinfo_option =
    NI_NOFQDN            (** Do not qualify local host names *)
  | NI_NUMERICHOST       (** Always return host as IP address *)
  | NI_NAMEREQD          (** Fail if host name cannot be determined *)
  | NI_NUMERICSERV       (** Always return service as port number *)
  | NI_DGRAM             (** Consider the service as UDP-based
                             instead of the default TCP *)
(** Options to {!Unix.getnameinfo}. *)

val getnameinfo : sockaddr -> getnameinfo_option list -> name_info
(** [getnameinfo addr opts] returns the host name and service name
    corresponding to the socket address [addr].  [opts] is a possibly
    empty list of options that governs how these names are obtained.
    Raise [Not_found] if an error occurs. *)


(** {6 Terminal interface} *)


(** The following functions implement the POSIX standard terminal
   interface. They provide control over asynchronous communication ports
   and pseudo-terminals. Refer to the [termios] man page for a
   complete description. *)

type terminal_io =
  {
    (* input modes *)
    mutable c_ignbrk : bool;  (** Ignore the break condition. *)
    mutable c_brkint : bool;  (** Signal interrupt on break condition. *)
    mutable c_ignpar : bool;  (** Ignore characters with parity errors. *)
    mutable c_parmrk : bool;  (** Mark parity errors. *)
    mutable c_inpck : bool;   (** Enable parity check on input. *)
    mutable c_istrip : bool;  (** Strip 8th bit on input characters. *)
    mutable c_inlcr : bool;   (** Map NL to CR on input. *)
    mutable c_igncr : bool;   (** Ignore CR on input. *)
    mutable c_icrnl : bool;   (** Map CR to NL on input. *)
    mutable c_ixon : bool;    (** Recognize XON/XOFF characters on input. *)
    mutable c_ixoff : bool;   (** Emit XON/XOFF chars to control input flow. *)
    (* Output modes: *)
    mutable c_opost : bool;   (** Enable output processing. *)
    (* Control modes: *)
    mutable c_obaud : int;    (** Output baud rate (0 means close connection).*)
    mutable c_ibaud : int;    (** Input baud rate. *)
    mutable c_csize : int;    (** Number of bits per character (5-8). *)
    mutable c_cstopb : int;   (** Number of stop bits (1-2). *)
    mutable c_cread : bool;   (** Reception is enabled. *)
    mutable c_parenb : bool;  (** Enable parity generation and detection. *)
    mutable c_parodd : bool;  (** Specify odd parity instead of even. *)
    mutable c_hupcl : bool;   (** Hang up on last close. *)
    mutable c_clocal : bool;  (** Ignore modem status lines. *)
    (* Local modes: *)
    mutable c_isig : bool;    (** Generate signal on INTR, QUIT, SUSP. *)
    mutable c_icanon : bool;  (** Enable canonical processing
                                 (line buffering and editing) *)
    mutable c_noflsh : bool;  (** Disable flush after INTR, QUIT, SUSP. *)
    mutable c_echo : bool;    (** Echo input characters. *)
    mutable c_echoe : bool;   (** Echo ERASE (to erase previous character). *)
    mutable c_echok : bool;   (** Echo KILL (to erase the current line). *)
    mutable c_echonl : bool;  (** Echo NL even if c_echo is not set. *)
    (* Control characters: *)
    mutable c_vintr : char;   (** Interrupt character (usually ctrl-C). *)
    mutable c_vquit : char;   (** Quit character (usually ctrl-\). *)
    mutable c_verase : char;  (** Erase character (usually DEL or ctrl-H). *)
    mutable c_vkill : char;   (** Kill line character (usually ctrl-U). *)
    mutable c_veof : char;    (** End-of-file character (usually ctrl-D). *)
    mutable c_veol : char;    (** Alternate end-of-line char. (usually none). *)
    mutable c_vmin : int;     (** Minimum number of characters to read
                                 before the read request is satisfied. *)
    mutable c_vtime : int;    (** Maximum read wait (in 0.1s units). *)
    mutable c_vstart : char;  (** Start character (usually ctrl-Q). *)
    mutable c_vstop : char;   (** Stop character (usually ctrl-S). *)
  }

val tcgetattr : file_descr -> terminal_io
(** Return the status of the terminal referred to by the given
   file descriptor. *)

type setattr_when =
    TCSANOW
  | TCSADRAIN
  | TCSAFLUSH

val tcsetattr : file_descr -> setattr_when -> terminal_io -> unit
(** Set the status of the terminal referred to by the given
   file descriptor. The second argument indicates when the
   status change takes place: immediately ([TCSANOW]),
   when all pending output has been transmitted ([TCSADRAIN]),
   or after flushing all input that has been received but not
   read ([TCSAFLUSH]). [TCSADRAIN] is recommended when changing
   the output parameters; [TCSAFLUSH], when changing the input
   parameters. *)

val tcsendbreak : file_descr -> int -> unit
(** Send a break condition on the given file descriptor.
   The second argument is the duration of the break, in 0.1s units;
   0 means standard duration (0.25s). *)

val tcdrain : file_descr -> unit
(** Waits until all output written on the given file descriptor
   has been transmitted. *)

type flush_queue =
    TCIFLUSH
  | TCOFLUSH
  | TCIOFLUSH

val tcflush : file_descr -> flush_queue -> unit
(** Discard data written on the given file descriptor but not yet
   transmitted, or data received but not yet read, depending on the
   second argument: [TCIFLUSH] flushes data received but not read,
   [TCOFLUSH] flushes data written but not transmitted, and
   [TCIOFLUSH] flushes both. *)

type flow_action =
    TCOOFF
  | TCOON
  | TCIOFF
  | TCION

val tcflow : file_descr -> flow_action -> unit
(** Suspend or restart reception or transmission of data on
   the given file descriptor, depending on the second argument:
   [TCOOFF] suspends output, [TCOON] restarts output,
   [TCIOFF] transmits a STOP character to suspend input,
   and [TCION] transmits a START character to restart input. *)

val setsid : unit -> int
(** Put the calling process in a new session and detach it from
   its controlling terminal. *)
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.