getpw - reconstruct password line entry


   #define _GNU_SOURCE             /* See feature_test_macros(7) */
   #include <sys/types.h>
   #include <pwd.h>

   int getpw(uid_t uid, char *buf);


   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


   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).


   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.


   0 or ENOENT
          No user corresponding to uid.

   EINVAL buf is NULL.

   ENOMEM Insufficient memory to allocate passwd structure.


          password database file


   For   an   explanation   of   the  terms  used  in  this  section,  see

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




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


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


   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


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