Xau(3)Xau(3)NAME
Xau library: XauFileName, XauReadAuth, XauLockAuth, XauUn-
lockAuth, XauWriteAuth, XauDisposeAuth, XauGetAuthByAddr,
XauGetBestAuthByAddr - 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 (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;
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Xau(3)Xau(3)
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 (e.g., 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 syn-
chronization 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 time-
out seconds between each attempt. XauLockAuth returns a
collection of values 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.
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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 autho-
rization entry.
SEE ALSOxauth(1), xdm(1)AUTHOR
Keith Packard, MIT X Consortium
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