.\" $NetBSD: getpwent.3,v 1.15 1999/04/25 13:45:02 lukem Exp $ .\" .\" Copyright (c) 1988, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)getpwent.3 8.2 (Berkeley) 12/11/93 .\" .Dd April 25, 1999 .Dt GETPWENT 3 .Os .Sh NAME .Nm getpwent , .Nm getpwnam , .Nm getpwuid , .Nm setpassent , .Nm setpwent , .Nm endpwent .Nd password database operations .Sh LIBRARY .Lb libc .Sh SYNOPSIS .Fd #include .Fd #include .Ft struct passwd * .Fn getpwent void .Ft struct passwd * .Fn getpwnam "const char *login" .Ft struct passwd * .Fn getpwuid "uid_t uid" .Ft int .Fn setpassent "int stayopen" .Ft void .Fn setpwent void .Ft void .Fn endpwent void .Sh DESCRIPTION These functions operate on the password database file which is described in .Xr passwd 5 . Each entry in the database is defined by the structure .Ar passwd found in the include file .Aq Pa pwd.h : .Bd -literal -offset indent 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 */ }; .Ed .Pp The functions .Fn getpwnam and .Fn getpwuid search the password database for the given login name or user uid, respectively, always returning the first one encountered. .Pp The .Fn getpwent function sequentially reads the password database and is intended for programs that wish to process the complete list of users. .Pp The .Fn setpassent function accomplishes two purposes. First, it causes .Fn getpwent to ``rewind'' to the beginning of the database. Additionally, if .Fa stayopen is non-zero, file descriptors are left open, significantly speeding up subsequent accesses for all of the functions. (This latter functionality is unnecessary for .Fn getpwent as it doesn't close its file descriptors by default.) .Pp 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. .Pp The .Fn setpwent function is equivalent to .Fn setpassent with an argument of zero. .Pp The .Fn endpwent function closes any open files. .Pp These functions 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 .Ql * . .Sh RETURN VALUES The functions .Fn getpwent , .Fn getpwnam , and .Fn 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 .Fn setpassent function returns 0 on failure and 1 on success. The .Fn endpwent and .Fn setpwent functions have no return value. .Sh FILES .Bl -tag -width /etc/master.passwd -compact .It Pa /etc/pwd.db The insecure password database file .It Pa /etc/spwd.db The secure password database file .It Pa /etc/master.passwd The current password file .It Pa /etc/passwd A Version 7 format password file .El .Sh SEE ALSO .Xr getlogin 2 , .Xr getgrent 3 , .Xr nsswitch.conf 5 , .Xr passwd 5 , .Xr pwd_mkdb 8 , .Xr vipw 8 .Sh STANDARDS The .Fn getpwnam and .Fn getpwuid functions conform to .St -p1003.1-90 . .Sh HISTORY The .Nm getpwent , .Nm getpwnam , .Nm getpwuid , .Nm setpwent, and .Nm endpwent functions appeared in .At v7 . The .Nm setpassent function appeared in .Bx 4.3 Reno . .Sh BUGS The functions .Fn getpwent , .Fn getpwnam , and .Fn getpwuid , leave their results in an internal static object and return a pointer to that object. Subsequent calls to any of these functions will modify the same object. .Pp The functions .Fn getpwent , .Fn endpwent , .Fn setpassent , and .Fn setpwent are fairly useless in a networked environment and should be avoided, if possible. .Fn getpwent makes no attempt to suppress duplicate information if multiple sources are specified in .Xr nsswitch.conf 5 .Sh COMPATIBILITY The historic function .Fn setpwfile which allowed the specification of alternative password databases, has been deprecated and is no longer available.