Parent process obtains the sub-process exit status (2)

main. cpp:

# Include <unistd. h> <br/> # include <iostream> <br/> # include <sys/Wait. h> <br/> # include <stdlib. h> </P> <p> using namespace STD; </P> <p> int main () <br/>{< br/> int ret; <br/> ret = fork (); <br/> If (Ret> 0) {<br/> cout <"parent start/N "; <br/> int status; pid_t PID; <br/> pid = wait (& status); <br/> If (PID! = RET) {<br/> cout <"parent wait error (wait return PID:" <pid <", fork return PID:" <RET <") /n "; <br/> exit (1); <br/>}else {<br/> cout <" parent wait return (PID: "<pid <")/n "; <br/>}< br/> cout <" parent's child end-pid: "<pid <", status: "<status <Endl; <br/> If (wifexited (Status )) {<br/> cout <"> child exited, exit code =" <wexitstatus (Status) <Endl; <br/> If (wexitstatus (Status) = 1) {<br/> cout <"> child exec error/N"; <br/>}< br/>} else if (wifsignaled (Status )) {<br/> cout <"> child killed (signal" <wtermsig (Status) <")/n "; <br/> # ifdef wcoredump <br/>} else if (wcoredump (Status) {<br/> cout <"> child core file generated/N "; <br/> # endif <br/>} else if (wifstopped (Status )) {<br/> cout <"> child stopped (signal" <wstopsig (Status) <")/n "; <br/> # ifdef wifcontinued <br/>} else if (wifcontinued (Status) {<br/> cout <"> child continued/N "; <br/> # endif <br/>} else {<br/> cout <"> unexpected status (" <status <")/n "; <br/>}< br/>} else if (ret = 0) {<br/> pid_t ppid = getppid (); <br/> cout <"Child start/N"; <br/> cout <"Child ppid:" <ppid <Endl; <br/> cout <"Child PID:" <getpid () <Endl; <br/> cout <"Child exec/N "; <br/> If (execl (". /child "," child ", (char *) 0) <0) {<br/> cout <" Child exec error/N "; <br/> exit (1); <br/>}< br/>} else {<br/> cout <"fork error/N "; <br/>}< br/> return 0; <br/>}

 

 

 

 

Child. cpp :( g ++ child. cpp-o child)

# Include <unistd. h> <br/> # include <iostream> <br/> using namespace STD; <br/> int main () <br/>{ <br/> cout <"Child exec start/N"; <br/> cout <"Child exec ppid:" <getppid () <Endl; <br/> cout <"Child exec PID:" <getpid () <Endl; <br/> sleep (30 ); <br/> return 0; <br/>}