strbufs has some invariants that are very important to keep in mind:
-. The `buf` member is never NULL, so
you it can be used in any usual C
+. The `buf` member is never NULL, so it can be used in any usual C
string operations safely. strbuf's _have_ to be initialized either by
`strbuf_init()` or by `= STRBUF_INIT` before the invariants, though.
-This is string buffer structure. The `len` member can be used to
+This is string buffer structure. The `len` member can be used to
determine the current length of the string, and `buf` member provides access to
comments are considered contents to be removed or not.
+ Launch the user preferred editor to edit a file and fill the buffer
+ with the file's contents upon the user completing their editing. The
+ third argument can be used to set the environment which the editor is
+ run in. If the buffer is NULL the editor is launched as usual but the
+ file's contents are not read into the buffer upon completion.