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_tpw_uid;
gid_tpw_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

getgrent(3C), getlogin(3C), passwd(4). 

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. 

  —  C Development Set