lckpwdf(3C)						   Standard C Library Functions 					       lckpwdf(3C)

NAME

       lckpwdf, ulckpwdf - manipulate shadow password database lock file

SYNOPSIS

       #include <shadow.h>

       int lckpwdf(void);

       int ulckpwdf(void);

DESCRIPTION

       The  lckpwdf()  and  ulckpwdf()	functions enable modification access to the password databases through the lock file. A process first uses
       lckpwdf() to lock the lock file, thereby gaining exclusive rights to modify  the   /etc/passwd  or   /etc/shadow  password  database.   See
       passwd(4) and shadow(4). Upon completing modifications, a process should release the lock on the lock file using ulckpwdf(). This mechanism
       prevents simultaneous modification of the password databases. The lock file, /etc/.pwd.lock, is used to coordinate modification	access	to
       the password databases /etc/passwd and  /etc/shadow.

RETURN VALUES

       If  lckpwdf()  is  successful in locking the file within 15 seconds, it returns 0. If unsuccessful (for example,  /etc/.pwd.lock is already
       locked), it returns -1.

       If ulckpwdf() is successful in unlocking the file  /etc/.pwd.lock, it returns 0. If unsuccessful (for example,  /etc/.pwd.lock  is  already
       unlocked), it returns -1.

USAGE

       These routines are for internal use only; compatibility is not guaranteed.

FILES

       /etc/passwd	       password database

       /etc/shadow	       shadow password database

       /etc/.pwd.lock	       lock file

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       getpwnam(3C), getspnam(3C), passwd(4), shadow(4), attributes(5)

SunOS 5.10							    29 Dec 1996 						       lckpwdf(3C)