1178 static FILE* __popen_fail(int fds[2]) {  in __popen_fail()
1180   close(fds[0]);  in __popen_fail()
1181   close(fds[1]);  in __popen_fail()
1187   int fds[2];  in popen()  local
1190     if (socketpair(AF_LOCAL, SOCK_CLOEXEC | SOCK_STREAM, 0, fds) == -1) return nullptr;  in popen()
1194     if (pipe2(fds, O_CLOEXEC) == -1) return nullptr;  in popen()
1211   if (fds[child] == desired_child_fd) {  in popen()
1212     int new_fd = fcntl(fds[child], F_DUPFD_CLOEXEC, 0);  in popen()
1213     if (new_fd == -1) return __popen_fail(fds);  in popen()
1214     close(fds[child]);  in popen()
1215     fds[child] = new_fd;  in popen()
1219   if (pid == -1) return __popen_fail(fds);  in popen()
1222     close(fds[parent]);  in popen()
1224     if (dup2(fds[child], desired_child_fd) == -1) _exit(127);  in popen()
1225     close(fds[child]);  in popen()
1231   FILE* fp = fdopen(fds[parent], mode);  in popen()
1232   if (fp == nullptr) return __popen_fail(fds);  in popen()
1234   close(fds[child]);  in popen()