#include <lcsignal.h> void sigchk(void);
sigchk is called to check for the occurrence of asynchronous
signals. If a signal is pending and not blocked, it is handled by the
handler defined by your program or by the default handler if none is
defined. If more than one signal is pending and not blocked, they are
processed in the order in which they occurred. However, for signals
managed by OpenEdition, the order in which they are discovered is
determined by OpenEdition. In this case, the first signal processed is
not necessarily the one that occurred first.
Since asynchronous signals are discovered only when a function is
called or returns, sigchk is useful for discovering these signals
in portions of code that do not call functions (for example, in the
middle of a lengthy calculation).
You can use the sigchk function to check for the occurrence of any
signal, whether managed by SAS/C or by OpenEdition. When a SAS/C handler
is defined for a signal, the timing of signal discovery is the same for
signals generated by OpenEdition as it is for signals generated by SAS/C.
That is, the signal is discovered only during a function call,
a function return, or a call to sigchk. However, if default handling
is specified for an OpenEdition signal, this action occurs as soon as the
signal is generated.
sigchk. It is not possible to
determine directly whether any signals were handled.
sigchk is a built-in function; that is, it is implemented by
compiler-generated code rather than as a true subroutine call. If no
signals are pending when sigchk is called, only two instructions
are executed.
sigchk to perform iterative computations
and checks for signals every 100 iterations:
#include <lcsignal.h>
for (i = 0; i < 10000; ) {
for (j = 0; j < 100; ++j,++i) {
/* Perform calculations. */
.
.
.
}
sigchk();
}
Copyright (c) 1998 SAS Institute Inc. Cary, NC, USA. All rights reserved.