我使用perl的open3运行命令,自定义命令的行为就像一个shell,它接受输入并显示输出,并等待另一个输入,直到给出退出
现在,我必须使用相同的命令并用C语言编写它,我们是否在C或C ++中具有类似于IPC :: Open3的功能?
最佳答案
popen()支持单向通信。如果要进行双向数据交换,则需要2个管道。 Jeff Epler提出了以下双向popen2.c实现:
#include <sys/types.h>
#include <unistd.h>
struct popen2 {
pid_t child_pid;
int from_child, to_child;
};
int popen2(const char *cmdline, struct popen2 *childinfo) {
pid_t p;
int pipe_stdin[2], pipe_stdout[2];
if(pipe(pipe_stdin)) return -1;
if(pipe(pipe_stdout)) return -1;
printf("pipe_stdin[0] = %d, pipe_stdin[1] = %d\n", pipe_stdin[0], pipe_stdin[1]);
printf("pipe_stdout[0] = %d, pipe_stdout[1] = %d\n", pipe_stdout[0], pipe_stdout[1]);
p = fork();
if(p < 0) return p; /* Fork failed */
if(p == 0) { /* child */
close(pipe_stdin[1]);
dup2(pipe_stdin[0], 0);
close(pipe_stdout[0]);
dup2(pipe_stdout[1], 1);
execl("/bin/sh", "sh", "-c", cmdline, 0);
perror("execl"); exit(99);
}
childinfo->child_pid = p;
childinfo->to_child = pipe_stdin[1];
childinfo->from_child = pipe_stdout[0];
return 0;
}
#define TESTING
#ifdef TESTING
int main(void) {
char buf[1000];
struct popen2 kid;
popen2("tr a-z A-Z", &kid);
write(kid.to_child, "testing\n", 8);
close(kid.to_child);
memset(buf, 0, 1000);
read(kid.from_child, buf, 1000);
printf("kill(%d, 0) -> %d\n", kid.child_pid, kill(kid.child_pid, 0));
printf("from child: %s", buf);
printf("waitpid() -> %d\n", waitpid(kid.child_pid, NULL, 0));
printf("kill(%d, 0) -> %d\n", kid.child_pid, kill(kid.child_pid, 0));
return 0;
}
#endif