uniq(1) doesn't trap file write error.

[Takehiko NOZAKI]

uniq(1) doesn't trap I/O error expect fopen(3).

first, fgetln(3) return NULL not only EOF but I/O error, so it should be checked by ferror(3).

       while ((p = fgetln(ifp, &psize)) != NULL) {
...
        }
       show(ofp, prevline);
       free(prevline);

second, fprintf(3)'s return value never checked:

       if ((dflag && repeats == 0) || (uflag && repeats > 0))
               return;
       if (cflag) {
               (void)fprintf(ofp, "%4d %s", repeats + 1, str);
       } else {
               (void)fprintf(ofp, "%s", str);

[Takehiko NOZAKI]

import new 2-claus BSDL uniq(1) implementation, for following PR: BUGFIX: Issue #108 - uniq(1) doesn't recognize '-' as stdin. BUGFIX: Issue #109 - uniq(1) use isspace(3b) instead of isblank(3) to parse field separator. BUGFIX: Issue #110 - uniq(1) doesn't trap file write error. ENHANCEMENT: Issue #106 - implement GNU uniq(1) extension.

→ <<cset 4d704feba757>>