c - Can I send char* with sigqueue to another process -


here part of code in client program 

      union sigval toserver;           char *test = "dummy";       serverpid = atol(buf2);       toserver.sival_ptr = (void *)test;         // register server       if (sigqueue(serverpid, sigusr1, toserver) == -1) {  // register          fprintf(stderr," server isn't ready!\n");          return 1;       }

here handler in server program

      static void register_handler(int signo, siginfo_t* info, void *context) {           registeredprogramid = info->si_pid;        if(info->si_value.sival_ptr != null)        fprintf(stderr," sent value  = %s \n" ,(char *)info->si_value.sival_ptr);       }

there no error can't sent. prints weird.

no cannot.

you can send char*, receiving process doesn't have access memory of sending process , memory may mapped differently. when access memory address pointed received pointer result undefined (i.e. platform specific , not repeatable). result either kind of memory protection error or read memory contains random value.


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