XAUTH(1)            X Version 11 (Release 4)             XAUTH(1)



  NAME
       XauFileName, XauReadAuth, XauLockAuth, XauUnlockAuth,
       XauWriteAuth, XauGetAuthByAddr - X authority database
       routines


  SYNOPSIS
       #include <X11/Xauth.h>

       typedef struct xauth {
            unsigned short family;
            unsigned short address_length;
            char           *address;
            unsigned short number_length;
            char           *number;
            unsigned short name_length;
            char           *name;
            unsigned short data_length;
            char           *data;
       } Xauth;

       char *XauFileName ()

       Xauth *XauReadAuth (authfile)
            FILE *auth_file;

       int XauWriteAuth (authfile, auth)
            FILE *auth_file;
            Xauth *auth;

       Xauth *XauGetAuthByAddr (family,
                                addresslength, address,
                                numberlength, number)
            unsigned short family;
            unsigned short address_length;
            char *address;
            unsigned short number_length;
            char *number;

       int XauLockAuth (filename, retries, timeout, dead)


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            char *file_name;
            int retries;
            int timeout;
            long dead;

       int XauUnlockAuth (filename)
            char *file_name;

       XauDisposeAuth (auth)
            Xauth *auth;


  DESCRIPTION
       XauFileName generates the default authorization file name by
       first checking the XAUTHROTIY environment variable if set,
       else it returns $HOME/.Xauthority.  This name is statically
       allocated and should not be freed.

       XauReadAuth reads the next entry from auth_file.  The entry
       is not statically allocated and should be freed by calling
       XauDisposeAuth.

       XuWriteAuth writes an authorization entry to auth_file.  It
       returns 1 on success, 0 on failure.

       XauGetAuthByAddr searches for an entry which matches the
       given network address/display number pair.  The entry is not
       statically allocated and should be freed by calling
       XauDisposeAuth

       XauLockAuth does the work necessary to synchronously update
       an authorization file.  First it makes to file names, one
       with ``-c'' appended to file_name, the other with ``-l''
       appended.  If the ``-c'' file already exists and is more
       than dead seconds old, XauLockAuth removes it and the
       associated ``-l'' file.  To prevent possible synchronization
       troubles with NFS, a dead value of zero forces the files to
       be removed.  XauLockAuth makes retries attempts to create
       and link the file names, pausing timeout seconds between
       each attempt.  XauLockAuth returns a collection of values


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       depending on the results:

            LOCK_ERROR     A system error occurred, either a file_name
                           which is too long, or an unexpected failure from
                           a system call.  errno may prove useful.

            LOCK_TIMEOUT   retries attempts failed

            LOCK_SUCCESS   The lock succeeded.


       XauUnlockAuth undoes the work of XauLockAuth by unlinking
       both the ``-c'' and ``-l'' file names.

       XauDisposeAuth frees storage allocated to hold an
       authorization entry.

  SEE ALSO
       xauth(1), xdm(1)

  COPYRIGHT
       Copyright 1988, Massachusetts Institute of Technology.
       See X(1) for a full statement of rights and permissions.

  AUTHOR
       Keith Packard, MIT X Consortium
















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