NAME

getpwent, getpwuid, getpwnam, setpwent, endpwent, fgetpwent - manipulate password file entry

SYNOPSIS

#include <pwd.h>

struct passwd *getpwent (void);

struct passwd *getpwuid (uid_t uid);

struct passwd *getpwnam (const char *name);

void setpwent (void);

void endpwent (void);

struct passwd *fgetpwent (FILE *f);

DESCRIPTION

getpwent, getpwuid, and getpwnam each returns a pointer to an object with the following structure containing the broken-out fields of a line in the /etc/passwd file. Each line in the file contains a passwd structure, declared in the pwd.h header file:

struct passwd {
     char *pw_name;
     char *pw_passwd;
     uid_t     pw_uid;
     gid_t     pw_gid;
     char *pw_age;
     char *pw_comment;
     char *pw_gecos;
     char *pw_dir;
     char *pw_shell;
};

getpwent when first called returns a pointer to the first passwd structure in the file; thereafter, it returns a pointer to the next passwd structure in the file; so successive calls can be used to search the entire file. getpwuid searches from the beginning of the file until a numerical user id matching uid is found and returns a pointer to the particular structure in which it was found. getpwnam searches from the beginning of the file until a login 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 setpwent has the effect of rewinding the password file to allow repeated searches. endpwent may be called to close the password file when processing is complete.

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

FILES

/etc/passwd

SEE ALSO

getlogin(3C), getgrent(3C).
passwd(4) in the System Administrator's Reference Manual.

DIAGNOSTICS

getpwent, getpwnid, getpwnam, and fgetpwent return a null pointer on EOF or error.

NOTES

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