NAME

getgrent, getgrgid, getgrnam, setgrent, endgrent, fgetgrent − get group file entry

SYNOPSIS

#include <grp.h>

struct group ∗getgrent ( )

struct group ∗getgrgid (gid)
int gid;

struct group ∗getgrnam (name)
char ∗name;

void setgrent ( )

void endgrent ( )

struct group ∗fgetgrent (f)
FILE ∗f;

HP-UX COMPATIBILITY

Level: HP-UX/NUCLEUS

Origin: System V

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 /etc/group file.  Each line contains a “group” structure, defined in the <grp.h> header file. 

structgroup {
char∗gr_name;/∗ the name of the group ∗/
char∗gr_passwd;/∗ the encrypted group password ∗/
intgr_gid;/∗ the numerical group ID ∗/
char∗∗gr_mem;/∗ vector of pointers to member names ∗/
};

Getgrent when first called returns a pointer to the first group structure in the file; thereafter, it returns a pointer to the next group structure in the file; so, successive calls may be used to search the entire file.  Getgrgid searches from the beginning of the file until a numerical group id matching gid is found and returns a pointer to the particular structure in which it was found.  Getgrnam searches from the beginning of the file until a group name matching name is found and returns a pointer to the particular structure in which it was found.  If an end-of-file or an error is encountered on reading, these functions return a NULL pointer. 

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. 

Fgetgrent returns a pointer to the next group structure in the stream f, which matches the format of /etc/group. 

FILES

/etc/group

SEE ALSO

getlogin(3C), getpwent(3C), group(5). 

DIAGNOSTICS

A NULL pointer is returned on EOF or error. 

WARNING

The above routines use <stdio.h>, which causes them to increase the size of programs, not otherwise using standard I/O, more than might be expected. 

BUGS

All information is contained in a static area, so it must be copied if it is to be saved. 

Hewlett-Packard  —  last mod. May 11, 2021