Xau(3X) 																   Xau(3X)

NAME

       Xau, XauFileName, XauReadAuth, XauLockAuth, XauUnlockAuth, XauWriteAuth, XauGetAuthByAddr, XauGetBestAuthByAddr - X authority database rou-
       tines

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 (auth_file)
	       FILE *auth_file;

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

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

       Xauth *XauGetBestAuthByAddr (family, address_length, address, number_length, number, types_length, types, type_lengths)
	       unsigned short family;
	       unsigned short address_length;
	       char *address;
	       unsigned short number_length;
	       char *number;
	       int types_length;
	       char **types;
	       int *type_lengths;

       int XauLockAuth (file_name, retries, timeout, dead)
	       char *file_name;
	       int retries;
	       int timeout;
	       long dead;

       int XauUnlockAuth (file_name)
	       char *file_name;

       XauDisposeAuth (auth)
	       Xauth *auth;

DESCRIPTION

       XauFileName generates the default authorization file name by first checking the XAUTHORITY 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.

       XauGetBestAuthByAddr is similar to XauGetAuthByAddr, except that a list of acceptable authentication methods is specified.  Xau will choose
       the  file  entry which matches the earliest entry in this list (for example, the most secure authentication method).  The types argument is
       an array of strings, one string for each authentication method.	 types_length  specifies  how  many  elements  are  in	the  types  array.
       types_lengths is an array of integers representing the length of each string.

       XauLockAuth  does the work necessary to synchronously update an authorization file.  First it makes two 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. XauLock-
       Auth makes retries attempts to create and link the file names, pausing timeout seconds between each attempt.  XauLockAuth returns a collec-
       tion  of  values  depending  on the results: A system error occurred, either a file_name which is too long, or an unexpected failure from a
       system call.  errno may prove useful.  gretries attempts failed.  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(1X), xdm(1X)

AUTHOR

       Keith Packard, MIT X Consortium

																	   Xau(3X)