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Diffstat (limited to 'lib/libc/gen/getpwent.3')
| -rw-r--r-- | lib/libc/gen/getpwent.3 | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/lib/libc/gen/getpwent.3 b/lib/libc/gen/getpwent.3 new file mode 100644 index 0000000..1208f53 --- /dev/null +++ b/lib/libc/gen/getpwent.3 @@ -0,0 +1,207 @@ +.\" 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 December 11, 1993 +.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 as 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 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 functions +.Fn setpassent +and +.Fn setpwent +return 0 on failure and 1 on success. +The +.Fn endpwent +function +has no return value. +.Sh FILES +.Bl -tag -width /etc/master.passwd -compact +.It Pa /var/db/pwd.db +The insecure password database file +.It Pa /var/db/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 3 , +.Xr getgrent 3 , +.Xr passwd 5 , +.Xr pwd_mkdb 8 , +.Xr vipw 8 +.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 +the same function +will modify the same object. +.Pp +The routines +.Fn getpwent , +.Fn endpwent , +.Fn setpassent , +and +.Fn setpwent +are fairly useless in a networked environment and should be +avoided, if possible. +.Sh COMPATIBILITY +The historic function +.Xr setpwfile 3 , +which allowed the specification of alternate password databases, +has been deprecated and is no longer available. |
