NAME    [Toc]    [Back]

     sockatmark - determine whether a socket is at the out-of-band mark

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <sys/socket.h>

     int
     sockatmark(int s);

DESCRIPTION    [Toc]    [Back]

     The sockatmark function determines whether the socket referenced by the
     file descriptor s is at the out-of-band mark.

RETURN VALUES    [Toc]    [Back]

     If successful, the sockatmark function returns 1 to indicate that the
     socket is at an out-of-band mark; 0 is returned if there is no out-ofband
 mark or the mark is preceeded by in-band data.  Otherwise, -1 is
     returned and errno is set to indicate the error.

ERRORS    [Toc]    [Back]

     The sockatmark function will fail if:

     [EBADF]            The argument s is not a valid file descriptor.

     [ENOTTY]           The file desciptor s does not refer to a socket.

SEE ALSO    [Toc]    [Back]

     ioctl(2), recv(2), socket(2)

     BSD Interprocess Communication Tutorial, reprinted in UNIX Programmer's
     Supplementary Documents Volume 1.

     Advanced 4.4BSD IPC Tutorial, reprinted in UNIX Programmer's
     Supplementary Documents Volume 1.

STANDARDS    [Toc]    [Back]

     The sockatmark function conforms to IEEE Std 1003.1g-2000 (``POSIX.1'').

HISTORY    [Toc]    [Back]

     The sockatmark function appeared in IEEE Std 1003.1g-2000 (``POSIX.1'')
     as a replacement for the SIOCATMARK ioctl(2) interface.

BSD                            October 22, 2001                            BSD