DOKK / manpages / debian 11 / libexplain-dev / explain_getresgid_or_die.3.en
explain_getresgid_or_die(3) Library Functions Manual explain_getresgid_or_die(3)

explain_getresgid_or_die - get r/e/s group IDs and report errors

#include <libexplain/getresgid.h>

void explain_getresgid_or_die(gid_t *rgid, gid_t *egid, gid_t *sgid);
int explain_getresgid_on_error(gid_t *rgid, gid_t *egid, gid_t *sgid);

The explain_getresgid_or_die function is used to call the getresgid(2) system call. On failure an explanation will be printed to stderr, obtained from the explain_getresgid(3) function, and then the process terminates by calling exit(EXIT_FAILURE).

The explain_getresgid_on_error function is used to call the getresgid(2) system call. On failure an explanation will be printed to stderr, obtained from the explain_getresgid(3) function, but still returns to the caller.

The rgid, exactly as to be passed to the getresgid(2) system call.
The egid, exactly as to be passed to the getresgid(2) system call.
The sgid, exactly as to be passed to the getresgid(2) system call.

The explain_getresgid_or_die function only returns on success, see getresgid(2) for more information. On failure, prints an explanation and exits, it does not return.

The explain_getresgid_on_error function always returns the value return by the wrapped getresgid(2) system call.

The explain_getresgid_or_die function is intended to be used in a fashion similar to the following example:

explain_getresgid_or_die(rgid, egid, sgid);

getresgid(2)
get real, effective and saved group IDs
explain_getresgid(3)
explain getresgid(2) errors
exit(2)
terminate the calling process

libexplain version 1.4
Copyright (C) 2012 Peter Miller