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getpw(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 4.09 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/.



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