bash/cmd and CTRL-C problem...

Michael Rumpf michael@rumpfonline.de
Wed Dec 19 13:41:00 GMT 2001


Hi,

I'm new to the list and I don't know if this problem is already solved, but
I couldn't find a hint neither on the archives nor on the FAQ or somewhere
else on the net.

My problem is related to bash/cmd and signal handling.
In my app I installed a signal handler for SIGINT. The app is going into a
wait loop and waiting for the exit flag from the signal handler to be set.

When pressing CTRL-C in the windows cmd shell the application continues
normally after the signal handler has been caught. Under bash the signal
handler is also correctly called, but after that the app is exiting
immediatly, i.e. not continuing with the code.
Here is the source:

////////////////////////////////////////////////////////////////////////////
/////////////////
#include <windows.h>
#include <stdio.h>
#include <signal.h>

bool loop = true;

extern "C" void signalHandler(int sig)
{
   switch( sig )
   {
      case SIGINT:  // == 2
         printf("SIGINT=%d\n",sig);
         break;
      default:
         printf("default=%d\n",sig);
         break;
   };
   loop=false;
}

int main(int argc, char* argv[])
{
   if (signal( SIGINT , signalHandler ) == SIG_ERR)
      return -1;
   printf("### ctrlbreak: Waiting now...\n");
   while(loop)
     Sleep ((DWORD) 1000) ;
   printf("### ctrlbreak: Finished waiting now...\n");
   return 0;
}
////////////////////////////////////////////////////////////////////////////
/////////////////

Here the the output of the app under Win2K/bash:
// bash                2.05a-2
$ ./ctrlbreak.exe
### ctrlbreak: Waiting now...
SIGINT=2


// GNU bash, version 2.02.1(2)-release (i586-pc-cygwin32) B20.1
bash-2.02$ ./ctrlbreak
### ctrlbreak: Waiting now...
SIGINT=2

// cmd.exe Win2k SP2
### ctrlbreak: Waiting now...
SIGINT=2
### ctrlbreak: Finished waiting now...


You can see that under the cmd shell the text "Finished waiting now..." is
printed which does not come out under the bash.
Any hint would be greatly appreciated...

Michael

PS: I just downloaded the latest stable version 1.3.6 today...




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