How to send signal from child under certain condition?
0
I created a program. It is supposed to read signals from second terminal window and react depending on which signal and to which process it is sent. For example, my child process 1 should ignore all signals but SIGUSR1 and SIGXFSZ. When SIGUSR1 is called, it should print some information (which i did) and end. However, when SIGXFSZ is called, it should send the same signal to parrent process. How can I do that?
Should
if(sig == SIGXFSZ) {
kill(number, getppid()); //where number is number for SIGXFSZ signal
}
placed in sig_handler function work?
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
void signals_handler(int signal){
psignal(signal,"nOtrzymalem sygnal");
printf("Numer sygnalu to: %dn", signal);
kill(getppid(), signal);
return;
}
void sig_handler (int sig){
signal(SIGUSR1, sig_handler);
sigset_t mask_set;
sigset_t old_set;
sigfillset(&mask_set);
sigdelset(&mask_set, SIGINT);
// sigdelset(&mask_set, SIGUSR1);
sigprocmask(SIG_SETMASK, &mask_set, &old_set);
// psignal(sig, "nOdebralem sygnal");
printf("Numer sygnału: %d. ^C mnie nie zamknie! %dn", sig, getppid());
printf("HEHHEHEHEHE");
for (;;)
pause(); //czy teraz zostanie przyjęty i obsłużony SIGUSR1?
sigprocmask(SIG_SETMASK, &old_set, NULL);
return;
}
int main(void) {
printf("PID: %dn", getpid());
/* zastawiamy "pulapke" na sygnal */
signal(SIGINT, signals_handler);
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
/* petla nieskonczona */
for(;;)
pause();
return 0;
}
c unix signals fork kill
asked Nov 21 '18 at 18:15
MichałMichał
13
add a comment |
0
I created a program. It is supposed to read signals from second terminal window and react depending on which signal and to which process it is sent. For example, my child process 1 should ignore all signals but SIGUSR1 and SIGXFSZ. When SIGUSR1 is called, it should print some information (which i did) and end. However, when SIGXFSZ is called, it should send the same signal to parrent process. How can I do that?
Should
if(sig == SIGXFSZ) {
kill(number, getppid()); //where number is number for SIGXFSZ signal
}
placed in sig_handler function work?
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
void signals_handler(int signal){
psignal(signal,"nOtrzymalem sygnal");
printf("Numer sygnalu to: %dn", signal);
kill(getppid(), signal);
return;
}
void sig_handler (int sig){
signal(SIGUSR1, sig_handler);
sigset_t mask_set;
sigset_t old_set;
sigfillset(&mask_set);
sigdelset(&mask_set, SIGINT);
// sigdelset(&mask_set, SIGUSR1);
sigprocmask(SIG_SETMASK, &mask_set, &old_set);
// psignal(sig, "nOdebralem sygnal");
printf("Numer sygnału: %d. ^C mnie nie zamknie! %dn", sig, getppid());
printf("HEHHEHEHEHE");
for (;;)
pause(); //czy teraz zostanie przyjęty i obsłużony SIGUSR1?
sigprocmask(SIG_SETMASK, &old_set, NULL);
return;
}
int main(void) {
printf("PID: %dn", getpid());
/* zastawiamy "pulapke" na sygnal */
signal(SIGINT, signals_handler);
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
/* petla nieskonczona */
for(;;)
pause();
return 0;
}
c unix signals fork kill
asked Nov 21 '18 at 18:15
MichałMichał
13
It's not clear what you're after --signals_handler()andkill(getppid(), signal)will be run from the parent process, not from the children. The children will just printmnie nie zamknie, etc on receivingSIGUSR1.
– mosvy
Nov 22 '18 at 9:32
add a comment |
0
0
0
I created a program. It is supposed to read signals from second terminal window and react depending on which signal and to which process it is sent. For example, my child process 1 should ignore all signals but SIGUSR1 and SIGXFSZ. When SIGUSR1 is called, it should print some information (which i did) and end. However, when SIGXFSZ is called, it should send the same signal to parrent process. How can I do that?
Should
if(sig == SIGXFSZ) {
kill(number, getppid()); //where number is number for SIGXFSZ signal
}
placed in sig_handler function work?
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
void signals_handler(int signal){
psignal(signal,"nOtrzymalem sygnal");
printf("Numer sygnalu to: %dn", signal);
kill(getppid(), signal);
return;
}
void sig_handler (int sig){
signal(SIGUSR1, sig_handler);
sigset_t mask_set;
sigset_t old_set;
sigfillset(&mask_set);
sigdelset(&mask_set, SIGINT);
// sigdelset(&mask_set, SIGUSR1);
sigprocmask(SIG_SETMASK, &mask_set, &old_set);
// psignal(sig, "nOdebralem sygnal");
printf("Numer sygnału: %d. ^C mnie nie zamknie! %dn", sig, getppid());
printf("HEHHEHEHEHE");
for (;;)
pause(); //czy teraz zostanie przyjęty i obsłużony SIGUSR1?
sigprocmask(SIG_SETMASK, &old_set, NULL);
return;
}
int main(void) {
printf("PID: %dn", getpid());
/* zastawiamy "pulapke" na sygnal */
signal(SIGINT, signals_handler);
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
/* petla nieskonczona */
for(;;)
pause();
return 0;
}
c unix signals fork kill
asked Nov 21 '18 at 18:15
MichałMichał
13
I created a program. It is supposed to read signals from second terminal window and react depending on which signal and to which process it is sent. For example, my child process 1 should ignore all signals but SIGUSR1 and SIGXFSZ. When SIGUSR1 is called, it should print some information (which i did) and end. However, when SIGXFSZ is called, it should send the same signal to parrent process. How can I do that?
Should
if(sig == SIGXFSZ) {
kill(number, getppid()); //where number is number for SIGXFSZ signal
}
placed in sig_handler function work?
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
void signals_handler(int signal){
psignal(signal,"nOtrzymalem sygnal");
printf("Numer sygnalu to: %dn", signal);
kill(getppid(), signal);
return;
}
void sig_handler (int sig){
signal(SIGUSR1, sig_handler);
sigset_t mask_set;
sigset_t old_set;
sigfillset(&mask_set);
sigdelset(&mask_set, SIGINT);
// sigdelset(&mask_set, SIGUSR1);
sigprocmask(SIG_SETMASK, &mask_set, &old_set);
// psignal(sig, "nOdebralem sygnal");
printf("Numer sygnału: %d. ^C mnie nie zamknie! %dn", sig, getppid());
printf("HEHHEHEHEHE");
for (;;)
pause(); //czy teraz zostanie przyjęty i obsłużony SIGUSR1?
sigprocmask(SIG_SETMASK, &old_set, NULL);
return;
}
int main(void) {
printf("PID: %dn", getpid());
/* zastawiamy "pulapke" na sygnal */
signal(SIGINT, signals_handler);
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
if(fork() == 0) { //forking
printf("PPID: %dn", getpid());
signal(SIGUSR1, sig_handler);
sleep(100);
exit(0);
}
/* petla nieskonczona */
for(;;)
pause();
return 0;
}
c unix signals fork kill
c unix signals fork kill
asked Nov 21 '18 at 18:15
MichałMichał
13
asked Nov 21 '18 at 18:15
MichałMichał
13
asked Nov 21 '18 at 18:15
MichałMichał
13
asked Nov 21 '18 at 18:15
MichałMichał
13
asked Nov 21 '18 at 18:15
MichałMichał
13
13
It's not clear what you're after --signals_handler()andkill(getppid(), signal)will be run from the parent process, not from the children. The children will just printmnie nie zamknie, etc on receivingSIGUSR1.
– mosvy
Nov 22 '18 at 9:32
add a comment |
It's not clear what you're after --signals_handler()andkill(getppid(), signal)will be run from the parent process, not from the children. The children will just printmnie nie zamknie, etc on receivingSIGUSR1.
– mosvy
Nov 22 '18 at 9:32
It's not clear what you're after --
signals_handler() and kill(getppid(), signal) will be run from the parent process, not from the children. The children will just print mnie nie zamknie, etc on receiving SIGUSR1.– mosvy
Nov 22 '18 at 9:32
It's not clear what you're after --
signals_handler() and kill(getppid(), signal) will be run from the parent process, not from the children. The children will just print mnie nie zamknie, etc on receiving SIGUSR1.– mosvy
Nov 22 '18 at 9:32
add a comment |
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It's not clear what you're after --
signals_handler()andkill(getppid(), signal)will be run from the parent process, not from the children. The children will just printmnie nie zamknie, etc on receivingSIGUSR1.– mosvy
Nov 22 '18 at 9:32