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GETPWENT(3)              BSD Library Functions Manual              GETPWENT(3)

     endpwent, getpwent, getpwnam, getpwnam_r, getpwuid, getpwuid_r,
     setpassent, setpwent -- password database operations

     Standard C Library (libc, -lc)

     #include <pwd.h>


     struct passwd *

     struct passwd *
     getpwnam(const char *login);

     getpwnam_r(const char *login, struct passwd *pwd, char *buffer,
         size_t bufsize, struct passwd **result);

     struct passwd *
     getpwuid(uid_t uid);

     getuid_r(uid_t uid, struct passwd *pwd, char *buffer, size_t bufsize,
         struct passwd **result);

     setpassent(int stayopen);


     These functions operate on the password database file, which is described
     in passwd(5).  Each entry in the database is defined by the structure
     passwd, found in the include file <pwd.h>:

           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 */
                   int     pw_fields;      /* internal: fields filled in */

     The functions getpwnam() and getpwuid() search the password database for
     the given login name or user uid, respectively, always returning the
     first one encountered.

     All of these routines are thread-safe.  The getpwent(), getpwnam(), and
     getpwuid() routines return a pointer to a result managed by the system
     library in a thread-specific data structure.  Every thread has space for
     a pointer to a struct passwd and allocates its own storage for the
     result.  Neither previously returned values in memory nor a previously
     returned pointer value should be used by a thread after calling any one
     of these three routines.  Memory allocated by a thread is automatically
     released on subsequent calls by the same thread to any of these three
     routines, and when the thread exits.

     The functions getpwnam_r() and getpwuid_r() take additional arguments
     which supply storage space for the returned result.  The pwd parameter is
     a pointer to a struct passwd, which must be allocated by the caller.  The
     buffer parameter is a pointer to a block of memory with a size specified
     by bufsize.  This buffer is used to hold the values which are pointed to
     by values filled in the pwd structure.  Zero is returned on success.  If
     insufficient memory is supplied, these routines return ERANGE.

     The getpwent() function sequentially reads the password database and is
     intended for programs that wish to process the complete list of users.

     The setpassent() function accomplishes two purposes.  First, it causes
     getpwent() to ``rewind'' to the beginning of the database.  Additionally,
     if 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 getpwent(), as it doesn't close its file
     descriptors by default.)

     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.

     The setpwent() function is identical to setpassent() with an argument of
     zero, save that it does not return a status value.

     The endpwent() function closes any open files.

     As of Mac OS X 10.3, there are now different per-user behaviours of this
     function, based on the AuthenticationAuthority value stored for the
     queried user in DirectoryServices.

     If the queried user is still a legacy crypt password user or now has an
     AuthenticationAuthority value containing ``;basic;'', these routines will
     behave in their standard BSD fashion.  These functions will ``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 `*'.

     By default in Mac OS X 10.3 and later all users will have an Authentica-tionAuthority AuthenticationAuthority
     tionAuthority with the value ``;ShadowHash;''.  These users will have a
     visible password value of ``********''.  These functions will have no
     access to the encrypted password whatsoever.  Setting or changing an user
     password must be done entirely through the DirectoryService APIs for this
     default user.

     There also exists an ``Apple Password Server'' user whose password value
     is also ``********'' and with an AuthenticationAuthority that contains
     the value ";ApplePasswordServer;" among other data.  There is no getpwnam
     access to the password for this user either and again set/change password
     can be done through the DirectoryService API.

     Finally in support of local user caching there is a local cached user
     whose password is also ``********'' and has an AuthenticationAuthority
     value containing ``;LocalCachedUser;'' among other data.  These functions
     also provide no access to the password for this user and set/change pass-word password
     word functionality is through the DirectoryService API.

     The functions getpwent(), getpwnam(), and getpwuid() return a valid
     pointer to a passwd structure on success and a null pointer if end-of-file end-offile
     file is reached or an error occurs.  The setpassent() function returns 0
     on failure and 1 on success.  The endpwent() and setpwent() functions
     have no return value.

     /etc/pwd.db         The insecure password database file
     /etc/spwd.db        The secure password database file
     /etc/master.passwd  The current password file
     /etc/passwd         A Version 7 format password file

     #include <sys/types.h>
     #include <pwd.h>

     The include file <sys/types.h> is necessary for the getpwent, getpwnam,
     and getpwuid functions.


     The setpwent() function returns 0 on failure and 1 on success.

     getlogin(2), getgrent(3), yp(8), passwd(5), pwd_mkdb(8), vipw(8)

     The getpwent(), getpwnam(), getpwuid(), setpwent(), and endpwent() func-tions functions
     tions appeared in Version 7 AT&T UNIX.  The setpassent() function
     appeared in 4.3BSD-Reno.

     The historic function setpwfile(3), which allowed the specification of
     alternate password databases, has been deprecated and is no longer avail-able. available.

     The functions getpwent(), getpwnam(), and getpwuid() leave their results
     in internal thread-specific memory and return a pointer to that object.
     Subsequent calls to any of these three routines by the same thread will
     release the object and return a new pointer value.

BSD                           September 20, 1994                           BSD