C Parent/Child exit variable -


i working on program , learning parent/child processes. childprocess 

exit(variable);

in main() have:

signal(sigchld, chldhandler);

outside main() have:

void chldhandler(int sig) {  }

how access variable chldhandler?

you use wait() inside signal handler, passing in non-null pointer status.

int status; wait(&status);

to decode status, check see exited normally, use wexitstatus() macro:

if (wifexited(status)) {     int variable = wexitstatus(status);     /*...*/ }

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