NAME

SP_poll - checks amount of data ready to be read

SYNOPSIS

#include <sp.h>
int SP_poll( mailbox mbox);

DESCRIPTION

SP_poll is a way to poll a mailbox to see if any messages are available for receiving. The value returned will be < 0 if error, 0 if nothing is available, and the number of bytes waiting if something is there.

RETURN VALUES

Returns 0 if nothing is available or the number of bytes available, or one of the following errors ( < 0 ):

ILLEGAL_SESSION: The session specified by mbox is illegal. Usually because it is not active.

BUGS

None.

AUTHOR