Programming Forums - segfault using sigaction with gnu history

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segfault using sigaction with gnu history

i am writing a shell program with a history feature. i am reassigning sigint (ctrl-c) to print the history list. i am trying to use the gnu history library to manage the history, but it now segfaults on ctrl-c. here is the code:

setup signal handler;

struct sigaction handler;

sigfillset(&handler.sa_mask);

handler.sa_handler = handle_SIGINT;

sigaction(SIGINT, &handler, NULL);

signal handling function:

void handle_SIGINT(int signo)

{

        printf("sig\n");

}

now if the following line is in main, ctrl-c segfaults, if it is commented out, it works fine..

add_history(*args);

i think that some other sig handling stuff is getting setup with gnu history, but i dont know what..
any help would be appreciated, if more info is needed, let me know.

Well, if the problem goes away when you comment out a call to add_history(), a fairly strong possibility is that the call of add_history() is the cause of the problem ...... which would mean the problem has nothing to the signal handling (the signal handling works incorrectly as a side-effect of an error by add_history()).

You haven't really provided enough information, but my guess is that add_history() assumes something about "args" that you are not honouring in main().

thanks for the response.. i tracked down the problem...

the add_history function did not work well with the *args pointer.. it would complile and execute once fine, but segfault.. fixed by assigning *args contents to buffer var and passing this in to add_history.