+.\" 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 6.8 (Berkeley) 4/19/91
+.\"
+.Dd April 19, 1991
+.Dt GETPWENT 3
+.Os
+.Sh NAME
+.Nm getpwent ,
+.Nm getpwnam ,
+.Nm getpwuid ,
+.Nm setpassent ,
+.Nm setpwent ,
+.Nm endpwent
+.Nd password database operations
+.Sh SYNOPSIS
+.Fd #include <sys/types.h>
+.Fd #include <pwd.h>
+.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 int
+.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 routines.
+(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 the database will become out of date if it is updated while the
+program is running.
+.Pp
+The
+.Fn setpwent
+function
+is identical to
+.Fn setpassent
+with an argument of zero.
+.Pp
+The
+.Fn endpwent
+function
+closes any open files.
+.Pp
+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 retuned
+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 functions
+.Fn setpassent
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