Linux signal processing-control processes by sending signals

Requirements:

implement two programs mysignal, Mycontrl, Mycontrl to mysignal send SIGINT signal, control mysiganl whether the screen print "Hello,world" string.

Makefile

. Suffixes:. C. occ=gccsrcs1=mysignal.csrcs2=mycontrol.c    objs1=$ (SRCS1:.C=.O) objs2=$ (SRCS2:.C=.O) EXEC1= Mysignalexec2=mycontrolall: $ (OBJS1) $ (OBJS2)    $ (cc)-  o $ (EXEC1) $ (OBJS1)    $ (cc)-  o $ (EXEC2) $ (OBJS2)      @echo '-------------ok--------------'. C.O:    $ (CC)-G-  o [email protected]-C $< Clean:    rm-f $ (OBJS1 ) $ (OBJS2)    rm-f core*

//mysignal.c

#include <stdio.h> #include <stdlib.h> #include <signal.h>int status = 0;//Global, 1-print, 0-do not print void Catch_ Signal (int sign) {    switch [sign]    {case    SIGINT:        if (status = = 0)        {            status = 1;        }        else        {            status = 0;}}    } int signal1 (int signo, void (*func) (int)) {    struct sigaction Act, oact;    Act.sa_handler = func;    Sigemptyset (&act.sa_mask);    act.sa_flags = 0;    Return Sigaction (Signo, &act, &oact);} int main (int arg, char *args[]) {    signal1 (SIGINT, catch_signal);//Capture SIGINT signal while    (1)    {        if ( Status)//If status is 1, print the string "Hello"        {            puts ("Hello, World");        }        Sleep (1);    }    return 0;}

//MYCONTROL.C

#include <stdio.h> #include <stdlib.h> #include <signal.h>int main (int arg, char *args[]) {    if (arg < 2)//If there is no parameter, main returns    {        return-1;    } else    {        int pid = atoi (Args[1]);        Kill (PID, SIGINT);//Send SIGINT signal to the specified PID    }    return 0;}

Operating effect:

Linux signal processing-control processes by sending signals