hi all,
can anbody please tell me that why the control transfers to the
function f() and then g() and then again f() and so on, when
longjmp(jbuf[0],1) is called in main.

Here is the complete program.

#include <stdio.h>
#include <setjmp.h>
#include <signal.h>

#define SECOND 1000000

char stack1[4096];
char stack2[4096];

jmp_buf jbuf[2];

f()
{
int i=0;
while(1){
printf("in f (%d)\n",i++);
usleep(SECOND);
}
}

g()
{
int i=0;
while(1){
printf("in g (%d)\n",i++);
usleep(SECOND);
}
}


setup()
{
sigsetjmp(jbuf[0],1);
jbuf[0][0].__jmpbuf[JB_SP] = (unsigned) stack1 + 4096;
jbuf[0][0].__jmpbuf[JB_PC] = (unsigned) f;

sigsetjmp(jbuf[1],1);
jbuf[1][0].__jmpbuf[JB_SP] = (unsigned) stack2 + 4096;
jbuf[1][0].__jmpbuf[JB_PC] = (unsigned) g;

}

static toggle = 0;

void dispatch(int sig)
{
puts("in dispatch");
if (sigsetjmp(jbuf[toggle],1) == 1)
return;

puts("DISPATCH");
toggle = 1 - toggle;
siglongjmp(jbuf[toggle],1);
}


main()
{
signal(SIGALRM, dispatch);
setup();
ualarm(5*SECOND, 5*SECOND);
longjmp(jbuf[0],1);
}

aditya wrote:
Don't multi-post. Cross post if you really must, but then set
followups to your primary newsgroup. I have already seen this in
c.l.c and this is an annoyance.

You have already been told that your code is non-standard, and
system specific. Therefore you need to find a group that deals
with your particular system. This is not it.

--
"It is not a question of staying the course, but of changing
the course" - John Kerry, 2004-09-20
"Ask any boat owner the eventual result of continuing the
present course indefinitely" - C.B. Falconer, 2004-09-20

CBFalconer writes:

==
"It is not a question of staying the course, but of changing
the course" - John Kerry, 2004-09-20
"Ask any boat owner the eventual result of continuing the
present course indefinitely" - C.B. Falconer, 2004-09-20

How about asking the Space Shuttle pilot?