PWCACHE(3)

NAME
pwcache - cache password and group entries

LIBRARY
libc

SYNOPSIS
#include <pwd.h>
const char *
user_from_uid(unsigned long uid, int nouser);
#include <grp.h>
const char *
group_from_gid(unsigned long gid, int nogroup);

DESCRIPTION
The user_from_uid() function returns the user name associated with the argument uid. The user name is cached so that multiple calls with the same uid do not require additional calls to getpwuid(3). If there is no user associated with the uid, a pointer is returned to a string representation of the uid, unless the argument nouser is non-zero, in which case a NULL pointer is returned.

The group_from_gid() function returns the group name associated with the argument gid. The group name is cached so that multiple calls with the same gid do not require additional calls to getgrgid(3). If there is no group associated with the gid, a pointer is returned to a string representation of the gid, unless the argument nogroup is non-zero, in which case a NULL pointer is returned.

SEE ALSO
getgrgid(3), getpwuid(3)

HISTORY
The user_from_uid() and group_from_gid() functions first appeared in 4.4BSD.