Critical Sections

[Xarky]

Hi,
I am trying to learn Critical Sections. I have written a small
program. Source code problem below.

What the program is doing is disabling the CRTL-C signal in the
critical section. My problem is that when in the Critical Section I
press the CTRL-C signal more than once. As supposed nothing happens,
but when critical section ends, should it give me all the CTRL-C
signals pressed or just one (its giving me one)?

How should the exact implementation be?

I hope some one out there understands my problem.

Thanks in advance


/* Source Code */

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

int cnt;

void CTRL_C_Handler (int sig)
{
cnt++;
printf ("%d. Now we are in CTRL_C_Handler.\n", cnt);
(void) signal (SIGINT, CTRL_C_Handler);
} // end method CRTL_C_Handler

main()
{
system ("clear");

(void) signal (SIGINT, CTRL_C_Handler);
sigset_t masking;

cnt=0;
sigemptyset (&masking);
sigaddset (&masking, SIGINT);

if (sigprocmask (SIG_BLOCK, &masking, NULL) == -1)
printf ("An error encountered: %s.\n", strerror(errno));

printf ("Enterend in Critical Section. Last for 5 seconds.\n");
printf ("Pressing CTRL-C will be useless.\n");
sleep(5);

printf ("Critical Section is ending now.\n");
if (sigprocmask (SIG_UNBLOCK, &masking, NULL) == -1)
printf ("An error encountered: %s.\n", strerror(errno));

while(1); // infinite loop
} // end main

 

[Thomas Matthews]

Hi,
I am trying to learn Critical Sections. I have written a small
program. Source code problem below.

[code snipped]

Sorry, but the _standard_ C language has no facilities or support
for Critical Sections so it is off-topic for this newsgroup.

However, a better newsgroup to discuss this is as it is an advanced programming concept. Just remember that not
all computer systems in the world support Critical Sections. And
when you post to a newsgroup that isn't platform dependent, like
and you are posting issues
that apply to all computer systems in the world (or most of them).

Followups set.

--
Thomas Matthews

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Other sites:
http://www.josuttis.com -- C++ STL Library book

 

[Christopher Benson-Manica]

(xpost and followups ignored, since this is metatopical)

However, a better newsgroup to discuss this is news:comp.programming,

I would also suggest comp.unix.programmer, given the code that OP
posted.