NAME
getgrent, getgrgid, getgrnam, setgrent, endgrent - get group file entry
SYNOPSIS
#include <grp.h>
struct group *getgrent();
struct group *getgrgid(gid) int gid;
struct group *getgrnam(name) char *name;
int setgrent();
int endgrent();
DESCRIPTION
Getgrent, getgrgid and getgrnam each return pointers to an object with the following structure containing the broken-out fields of a line in the group file.
struct group { /* see getgrent(3) */
char *gr_name;
char *gr_passwd;
int gr_gid;
char **gr_mem;
};
The members of this structure are:
- gr_name
- The name of the group.
- gr_passwd
- The encrypted password of the group.
- gr_gid
- The numerical group-ID.
- gr_mem
- Null-terminated vector of pointers to the individual member names.
Getgrent simply reads the next line while getgrgid and getgrnam search until a matching gid or name is found (or until EOF is encountered). Each routine picks up where the others leave off so successive calls may be used to search the entire file.
A call to setgrent has the effect of rewinding the group file to allow repeated searches. Endgrent may be called to close the group file when processing is complete.
FILES
/etc/group
SEE ALSO
getlogin(3), getpwent(3), group(5)
DIAGNOSTICS
A null pointer (0) is returned on EOF or error.
BUGS
All information is contained in a static area so it must be copied if it is to be saved.