Signal Processing Chapter

Signal processing function Set one:

#include <signal.h>

typedef void (*sighandler_t) (int);

sighandler_t signal (int signum, sighandler_t handler);

Signal (SIGNUM,FUNC); return Sig_err On Error

Send signal:

The KILL function sends a signal to a process or process group, and the raise function transmits the signal to itself

#include <sys/types.h>
#include <signal.h>

int Kill (pid_t pid, int sig);

• Pid>0 send signal to PID
• Pid=0 all processes that send signals to the process group to which the sending process belongs
• Pid=-1 sends a signal to all processes (of course, must have permission to send)
• Pid<-1 a process that sends a signal to all processes that the sending process belongs to the process group Id=-pid

#include <signal.h>

int raise (int sig);

setting alarms and suspending processes

#include <unistd.h>

unsigned int alarm (unsigned int seconds); After seconds seconds, a SIGALRM signal is generated.

int pause (void); Suspends the calling process until a signal is captured. After snapping to a signal and processing, pause will return, return value: -1,errno=eintr

Signal Processing Chapter