sandbox/ostep/hw5/hw5_3.c

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2018-09-06 01:32:57 +00:00
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int
main(void)
{
int pipefd[2];
if (pipe(pipefd) == -1) {
perror("pipe");
exit(1);
}
pid_t pid = fork();
if (pid < 0) {
perror("fork");
exit(1);
}
else if (pid > 0) {
close(pipefd[1]);
char buf[1];
read(pipefd[0], buf, 1);
printf("goodbye\n");
}
else {
sleep(1);
close(pipefd[0]);
printf("hello\n");
close(pipefd[1]);
}
}