+static void pager_open(void) {
+ pid_t pid;
+ int fd[2];
+ const char *pager;
+
+ if (!on_tty() || arg_no_pager)
+ return;
+
+ if ((pager = getenv("PAGER")))
+ if (!*pager || streq(pager, "cat"))
+ return;
+
+ if (pipe(fd) < 0) {
+ log_error("Failed to create pager pipe: %m");
+ return;
+ }
+
+ pid = fork();
+ if (pid < 0) {
+ log_error("Failed to fork pager: %m");
+ close_pipe(fd);
+ return;
+ }
+
+ /* The original process turns into the PAGER */
+ if (pid != 0) {
+
+ dup2(fd[0], STDIN_FILENO);
+ close_pipe(fd);
+
+ if (!getenv("LESS"))
+ setenv("LESS", "FRSX", 0);
+
+ if (pager) {
+ execlp(pager, pager, NULL);
+ execl("/bin/sh", "sh", "-c", pager, NULL);
+ } else {
+ execlp("sensible-pager", "sensible-pager", NULL);
+ execlp("less", "less", NULL);
+ execlp("more", "more", NULL);
+ }
+
+ log_error("Unable to execute pager: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ /* Return in the child */
+ if (dup2(fd[1], STDOUT_FILENO) < 0)
+ log_error("Failed to duplicate pager pipe: %m");
+
+ close_pipe(fd);
+}
+