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GETPWENT(3)	       FreeBSD Library Functions Manual		   GETPWENT(3)

NAME
     getpwent, getpwnam, getpwuid, setpassent, setpwent, endpwent -- password
     database operations

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <pwd.h>

     struct passwd *
     getpwent(void);

     struct passwd *
     getpwnam(const char *login);

     struct passwd *
     getpwuid(uid_t uid);

     int
     setpassent(int stayopen);

     void
     setpwent(void);

     void
     endpwent(void);

DESCRIPTION
     These functions operate on	the password database file which is described
     in	passwd(5).  Each entry in the database is defined by the structure
     passwd found in the include file <pwd.h>:

	   struct passwd {
		   char	   *pw_name;	   /* user name	*/
		   char	   *pw_passwd;	   /* encrypted	password */
		   uid_t   pw_uid;	   /* user uid */
		   gid_t   pw_gid;	   /* user gid */
		   time_t  pw_change;	   /* password change time */
		   char	   *pw_class;	   /* user access class	*/
		   char	   *pw_gecos;	   /* Honeywell	login info */
		   char	   *pw_dir;	   /* home directory */
		   char	   *pw_shell;	   /* default shell */
		   time_t  pw_expire;	   /* account expiration */
		   int	   pw_fields;	   /* internal:	fields filled in */
	   };

     The functions getpwnam() and getpwuid() search the	password database for
     the given login name or user uid, respectively, always returning the
     first one encountered.

     The getpwent() function sequentially reads	the password database and is
     intended for programs that	wish to	process	the complete list of users.

     The setpassent() function accomplishes two	purposes.  First, it causes
     getpwent()	to ``rewind'' to the beginning of the database.	 Additionally,
     if	stayopen is non-zero, file descriptors are left	open, significantly
     speeding up subsequent accesses for all of	the routines.  (This latter
     functionality is unnecessary for getpwent() as it doesn't close its file
     descriptors by default.)

     It	is dangerous for long-running programs to keep the file	descriptors
     open as the database will become out of date if it	is updated while the
     program is	running.

     The setpwent() function is	identical to setpassent() with an argument of
     zero.

     The endpwent() function closes any	open files.

     These routines have been written to ``shadow'' the	password file, e.g.
     allow only	certain	programs to have access	to the encrypted password.  If
     the process which calls them has an effective uid of 0, the encrypted
     password will be returned,	otherwise, the password	field of the returned
     structure will point to the string	`*'.

YP/NIS INTERACTION
     When the yp(8) password database is enabled, the getpwnam() and
     getpwuid()	functions use the YP maps ``passwd.byname'' and
     ``passwd.byuid'', respectively, if	the requested password entry is	not
     found in the local	database.  The getpwent() function will	step through
     the YP map	``passwd.byname'' if the entire	map is enabled as described in
     passwd(5).

RETURN VALUES
     The functions getpwent(), getpwnam(), and getpwuid(), return a valid
     pointer to	a passwd structure on success and a null pointer if end-of-
     file is reached or	an error occurs.  The setpassent() function returns 0
     on	failure	and 1 on success.  The endpwent() and setpwent() functions
     have no return value.

FILES
     /etc/pwd.db	 The insecure password database	file
     /etc/spwd.db	 The secure password database file
     /etc/master.passwd	 The current password file
     /etc/passwd	 A Version 7 format password file

SEE ALSO
     getlogin(2), getgrent(3), passwd(5), pwd_mkdb(8), vipw(8),	yp(8)

HISTORY
     The getpwent(), getpwnam(), getpwuid(), setpwent(), and endpwent()	func-
     tions appeared in Version 7 AT&T UNIX.  The setpassent() function
     appeared in 4.3BSD-Reno.

COMPATIBILITY
     The historic function setpwfile(3), which allowed the specification of
     alternate password	databases, has been deprecated and is no longer	avail-
     able.

BUGS
     The functions getpwent(), getpwnam(), and getpwuid(), leave their results
     in	an internal static object and return a pointer to that object.	Subse-
     quent calls to the	same function will modify the same object.

FreeBSD	10.1		      September	20, 1994		  FreeBSD 10.1

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | YP/NIS INTERACTION | RETURN VALUES | FILES | SEE ALSO | HISTORY | COMPATIBILITY | BUGS

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