I don't know when, but the alarm system call no longer works
properly. The following program works on Unix but not
Linux FC4t3 or FC3. This is the mechanism rz/sz use for
generating protocol timeouts.
#include <stdio.h>
#include <setjmp.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <termios.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <setjmp.h>
jmp_buf timedout; /* For the timeout interrupt on RX timeout */
void
alrm(c)
{
longjmp(timedout, -1);
}
char linbuf[33];
main()
{
int c;
int n = 4;
printf ("This program should time out every 4 seconds\n");
for (;;) {
printf("Calling read: alarm=%d \n ", n );
if (setjmp(timedout)) {
printf("Readline:TIMEOUT\n");
continue;
}
signal(SIGALRM, alrm);
alarm(n);
errno = 0;
c = read(0, linbuf, 22);
alarm(0);
printf("Read returned %d\n", n);
}
}
--
Chuck Forsberg caf@xxxxxxxx www.omen.com 503-614-0430
Developer of Industrial ZMODEM(Tm) for Embedded Applications
Omen Technology Inc "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231 FAX 629-0665