Linux manual pages Section 3  

Name

getpw — reconstruct password line entry

Synopsis

#define _GNU_SOURCE              /* See feature_test_macros(7) */
#include <sys/types.h>
#include <pwd.h>
int getpw( uid_t uid,
  char *buf);
 

DESCRIPTION

The getpw() function reconstructs the password line entry for the given user ID uid in the buffer buf. The returned buffer contains a line of format

name:passwd:uid:gid:gecos:dir:shell

The passwd structure is defined in <pwd.h> as follows:

struct passwd {
  char * pw_name;
/* username */
  char * pw_passwd;
/* user password */
  uid_t   pw_uid;
/* user ID */
  gid_t   pw_gid;
/* group ID */
  char * pw_gecos;
/* user information */
  char * pw_dir;
/* home directory */
  char * pw_shell;
/* shell program */
};

For more information about the fields of this structure, see passwd(5).

RETURN VALUE

The getpw() function returns 0 on success; on error, it returns −1, and errno is set to indicate the error.

If uid is not found in the password database, getpw() returns −1, sets errno to 0, and leaves buf unchanged.

ERRORS

0 or ENOENT

No user corresponding to uid.

EINVAL

buf is NULL.

ENOMEM

Insufficient memory to allocate passwd structure.

FILES

/etc/passwd

password database file

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
getpw() Thread safety MT-Safe locale

CONFORMING TO

SVr2.

BUGS

The getpw() function is dangerous as it may overflow the provided buffer buf. It is obsoleted by getpwuid(3).

SEE ALSO

endpwent(3), fgetpwent(3), getpwent(3), getpwnam(3), getpwuid(3), putpwent(3), setpwent(3), passwd(5)

COLOPHON

This page is part of release 4.07 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man−pages/.


  Copyright 1993 David Metcalfe (davidprism.demon.co.uk)

%%%LICENSE_START(VERBATIM)
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided that the
entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Since the Linux kernel and libraries are constantly changing, this
manual page may be incorrect or out-of-date.  The author(s) assume no
responsibility for errors or omissions, or for damages resulting from
the use of the information contained herein.  The author(s) may not
have taken the same level of care in the production of this manual,
which is licensed free of charge, as they might when working
professionally.

Formatted or processed versions of this manual, if unaccompanied by
the source, must acknowledge the copyright and authors of this work.
%%%LICENSE_END

References consulted:
    Linux libc source code
    Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
    386BSD man pages
Modified Sat Jul 24 19:23:25 1993 by Rik Faith (faithcs.unc.edu)
Modified Mon May 27 21:37:47 1996 by Martin Schulze (joeylinux.de)