* src/groupmems.c: Check the return value of gr_update().

* src/chage.c, src/chfn.c, src/chgpasswd.c, src/chpasswd.c,
	src/chsh.c, src/gpasswd.c, src/groupadd.c, src/groupmems.c,
	src/groupmod.c, src/grpck.c, src/grpconv.c, src/grpunconv.c,
	src/passwd.c, src/pwck.c, src/pwconv.c, src/pwunconv.c,
	src/useradd.c, src/userdel.c, src/usermod.c: Harmonize the error
	message sent to stderr in case of *_update () failure.
	* src/chage.c, src/chsh.c, src/groupadd.c, src/passwd.c: Do not
	log to syslog when pw_update() or spw_update() fail.
	* src/newusers.c: Do not log specific error message to stderr when
	sgr_update() fails.
	* src/pwconv.c: Remove duplicated definition of Prog.

src/newusers.c

@@ -275,9 +275,6 @@ static int add_group (const char *name, const char *gid, gid_t *ngid, uid_t uid)
 		sgrent.sg_mem = members;
 
 		if (sgr_update (&sgrent) == 0) {
-			fprintf (stderr,
-			         _("%s: group %s created, failure during the creation of the corresponding gshadow group\n"),
-			         Prog, grent.gr_name);
 			return -1;
 		}
 	}