/* $OpenBSD: spawn.c,v 1.50 2026/07/23 09:38:27 nicm Exp $ */

/*
 * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/wait.h>

#include <errno.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>

#include "tmux.h"

/*
 * Set up the environment and create a new window and pane or a new pane.
 *
 * We need to set up the following items:
 *
 * - history limit, comes from the session;
 *
 * - base index, comes from the session;
 *
 * - current working directory, may be specified - if it isn't it comes from
 *   either the client or the session;
 *
 * - PATH variable, comes from the client if any, otherwise from the session
 *   environment;
 *
 * - shell, comes from default-shell;
 *
 * - termios, comes from the session;
 *
 * - remaining environment, comes from the session.
 */

static void
spawn_log(const char *from, struct spawn_context *sc)
{
        struct session          *s = sc->s;
        struct winlink          *wl = sc->wl;
        struct window_pane      *wp0 = sc->wp0;
        const char              *name = (sc->name == NULL ? "none" : sc->name);
        char                     tmp[128];

        log_debug("%s: name=%s, flags=%#x", from, name, sc->flags);
        if (wl != NULL && wp0 != NULL)
                xsnprintf(tmp, sizeof tmp, "wl=%d wp0=%%%u", wl->idx, wp0->id);
        else if (wl != NULL)
                xsnprintf(tmp, sizeof tmp, "wl=%d wp0=none", wl->idx);
        else if (wp0 != NULL)
                xsnprintf(tmp, sizeof tmp, "wl=none wp0=%%%u", wp0->id);
        else
                xsnprintf(tmp, sizeof tmp, "wl=none wp0=none");
        log_debug("%s: s=$%u %s idx=%d", from, s->id, tmp, sc->idx);
}

static void
spawn_fire_pane_created(struct spawn_context *sc, struct window_pane *wp)
{
        struct event_payload    *ep;
        struct cmd_find_state    fs;
        char                    *cmd = NULL;
        const char              *cwd = wp->cwd;

        ep = event_payload_create();
        cmd_find_from_winlink_pane(&fs, sc->wl, wp, 0);
        event_payload_set_target(ep, &fs);
        event_payload_set_session(ep, "session", sc->s);
        event_payload_set_window(ep, "window", wp->window);
        event_payload_set_int(ep, "window_index", sc->wl->idx);
        event_payload_set_pane(ep, "pane", wp);

        if (wp->argc != 0)
                cmd = cmd_stringify_argv(wp->argc, wp->argv);
        if (cmd != NULL && *cmd != '\0')
                event_payload_set_string(ep, "pane_command", "%s", cmd);
        else if (wp->shell != NULL)
                event_payload_set_string(ep, "pane_command", "%s", wp->shell);
        free(cmd);

        if (cwd != NULL)
                event_payload_set_string(ep, "pane_current_path", "%s", cwd);

        if (sc->flags & SPAWN_EMPTY)
                event_payload_set_int(ep, "created_empty", 1);
        else
                event_payload_set_int(ep, "created_empty", 0);
        if (sc->flags & SPAWN_RESPAWN)
                event_payload_set_int(ep, "created_respawn", 1);
        else
                event_payload_set_int(ep, "created_respawn", 0);

        events_fire("pane-created", ep);
}

struct winlink *
spawn_window(struct spawn_context *sc, char **cause)
{
        struct session          *s = sc->s;
        struct window           *w;
        struct window_pane      *wp;
        struct winlink          *wl;
        int                      idx = sc->idx;
        u_int                    sx, sy, xpixel, ypixel;

        spawn_log(__func__, sc);

        /*
         * If the window already exists, we are respawning, so destroy all the
         * panes except one.
         */
        if (sc->flags & SPAWN_RESPAWN) {
                w = sc->wl->window;
                if (~sc->flags & SPAWN_KILL) {
                        TAILQ_FOREACH(wp, &w->panes, entry) {
                                if (wp->fd != -1)
                                        break;
                        }
                        if (wp != NULL) {
                                xasprintf(cause, "window %s:%d still active",
                                    s->name, sc->wl->idx);
                                return (NULL);
                        }
                }

                sc->wp0 = TAILQ_FIRST(&w->panes);
                TAILQ_REMOVE(&w->panes, sc->wp0, entry);

                layout_free(w, 0);
                window_destroy_panes(w);

                TAILQ_INSERT_HEAD(&w->panes, sc->wp0, entry);
                window_pane_resize(sc->wp0, w->sx, w->sy);

                layout_init(w, sc->wp0);
                w->active = NULL;
                window_set_active_pane(w, sc->wp0, 0);
        }

        /*
         * Otherwise we have no window so we will need to create one. First
         * check if the given index already exists and destroy it if so.
         */
        if ((~sc->flags & SPAWN_RESPAWN) && idx != -1) {
                wl = winlink_find_by_index(&s->windows, idx);
                if (wl != NULL && (~sc->flags & SPAWN_KILL)) {
                        xasprintf(cause, "index %d in use", idx);
                        return (NULL);
                }
                if (wl != NULL) {
                        /*
                         * Can't use session_detach as it will destroy session
                         * if this makes it empty.
                         */
                        wl->flags &= ~WINLINK_ALERTFLAGS;
                        events_fire_winlink("window-unlinked", wl);
                        winlink_stack_remove(&s->lastw, wl);
                        winlink_remove(&s->windows, wl);

                        if (s->curw == wl) {
                                s->curw = NULL;
                                sc->flags &= ~SPAWN_DETACHED;
                        }
                }
        }

        /* Then create a window if needed. */
        if (~sc->flags & SPAWN_RESPAWN) {
                if (idx == -1)
                        idx = -1 - options_get_number(s->options, "base-index");
                if ((sc->wl = winlink_add(&s->windows, idx)) == NULL) {
                        xasprintf(cause, "couldn't add window %d", idx);
                        return (NULL);
                }
                default_window_size(sc->tc, s, NULL, &sx, &sy, &xpixel, &ypixel,
                    -1);
                if ((w = window_create(sx, sy, xpixel, ypixel)) == NULL) {
                        winlink_remove(&s->windows, sc->wl);
                        xasprintf(cause, "couldn't create window %d", idx);
                        return (NULL);
                }
                if (s->curw == NULL)
                        s->curw = sc->wl;
                sc->wl->session = s;
                w->latest = sc->tc;
                winlink_set_window(sc->wl, w);
        } else
                w = NULL;
        sc->flags |= SPAWN_NONOTIFY;

        /* Spawn the pane. */
        wp = spawn_pane(sc, cause);
        if (wp == NULL) {
                if (~sc->flags & SPAWN_RESPAWN)
                        winlink_remove(&s->windows, sc->wl);
                return (NULL);
        }

        /* Set the name of the new window. */
        if (~sc->flags & SPAWN_RESPAWN) {
                free(w->name);
                if (sc->name == NULL)
                        w->name = default_window_name(w);
                else {
                        w->name = xstrdup(sc->name);
                        options_set_number(w->options, "automatic-rename", 0);
                }
                window_set_fill_cells(w);
        }

        /* Switch to the new window if required. */
        if (~sc->flags & SPAWN_DETACHED)
                session_select(s, sc->wl->idx);

        /* Fire notification if new window. */
        if (~sc->flags & SPAWN_RESPAWN) {
                events_fire_window("window-created", w);
                events_fire_winlink("window-linked", sc->wl);
        }

        session_group_synchronize_from(s);
        return (sc->wl);
}

struct window_pane *
spawn_pane(struct spawn_context *sc, char **cause)
{
        struct cmdq_item         *item = sc->item;
        struct client            *c;
        struct session           *s = sc->s;
        struct session           *ts;
        struct window            *w = sc->wl->window;
        struct window_pane       *new_wp;
        struct environ           *child;
        struct environ_entry     *ee;
        char                    **argv, *cp, **argvp, *argv0, *cwd, *new_cwd;
        char                      path[PATH_MAX];
        const char               *cmd, *tmp, *home = find_home();
        const char               *actual_cwd = NULL;
        int                       argc;
        u_int                     idx;
        struct termios            now;
        u_int                     hlimit;
        struct winsize            ws;
        sigset_t                  set, oldset;
        key_code                  key;

        if (item != NULL) {
                ts = cmdq_get_target(item)->s;
                c = cmdq_get_client(item);
        } else {
                ts = s;
                c = sc->tc;
        }

        spawn_log(__func__, sc);

        if (sc->flags & SPAWN_MODAL) {
                if (~sc->flags & SPAWN_FLOATING) {
                        xasprintf(cause, "modal pane must be floating");
                        return (NULL);
                }
                if (w->modal != NULL) {
                        xasprintf(cause, "window already has a modal pane");
                        return (NULL);
                }
        }

        /*
         * Work out the current working directory. If respawning, use
         * the pane's stored one unless specified.
         */
        if (sc->cwd != NULL) {
                if (item != NULL)
                        cwd = format_single(item, sc->cwd, c, ts, NULL, NULL);
                else
                        cwd = xstrdup(sc->cwd);
                if (*cwd != '/') {
                        xasprintf(&new_cwd, "%s%s%s",
                            server_client_get_cwd(c, ts),
                            *cwd != '\0' ? "/" : "", cwd);
                        free(cwd);
                        cwd = new_cwd;
                }
        } else if (~sc->flags & SPAWN_RESPAWN)
                cwd = xstrdup(server_client_get_cwd(c, ts));
        else
                cwd = NULL;

        /*
         * If we are respawning then get rid of the old process. Otherwise
         * either create a new cell or assign to the one we are given.
         */
        hlimit = options_get_number(s->options, "history-limit");
        if (sc->flags & SPAWN_RESPAWN) {
                if (sc->wp0->fd != -1 && (~sc->flags & SPAWN_KILL)) {
                        window_pane_index(sc->wp0, &idx);
                        xasprintf(cause, "pane %s:%d.%u still active",
                            s->name, sc->wl->idx, idx);
                        free(cwd);
                        return (NULL);
                }
                if (sc->wp0->event != NULL) {
                        bufferevent_free(sc->wp0->event);
                        sc->wp0->event = NULL;
                }
                if (sc->wp0->fd != -1) {
                        close(sc->wp0->fd);
                        sc->wp0->fd = -1;
                }
                window_pane_reset_mode_all(sc->wp0);
                screen_reinit(&sc->wp0->base);
                if (sc->wp0->ictx != NULL) {
                        input_free(sc->wp0->ictx);
                        sc->wp0->ictx = NULL;
                }
                new_wp = sc->wp0;
                new_wp->flags &= ~(PANE_STATUSREADY|PANE_STATUSDRAWN);
        } else {
                if (sc->lc == NULL) {
                        new_wp = window_add_pane(w, NULL, hlimit, sc->flags);
                        layout_init(w, new_wp);
                } else {
                        new_wp = window_add_pane(w, sc->wp0, hlimit, sc->flags);
                        if (sc->flags & SPAWN_ZOOM)
                                layout_assign_pane(sc->lc, new_wp, 1);
                        else
                                layout_assign_pane(sc->lc, new_wp, 0);
                }
                if (sc->flags & SPAWN_FLOATING)
                        new_wp->layout_cell->flags |= LAYOUT_CELL_FLOATING;

                /*
                 * If window currently zoomed, window_set_active_pane calls
                 * window_unzoom which it copies back the saved_layout_cell.
                 */
                if (w->flags & WINDOW_ZOOMED)
                        new_wp->saved_layout_cell = new_wp->layout_cell;
        }

        /*
         * Now we have a pane with nothing running in it ready for the new
         * process. Work out the command and arguments and store the working
         * directory.
         */
        if (sc->argc == 0 && (~sc->flags & SPAWN_RESPAWN)) {
                cmd = options_get_string(s->options, "default-command");
                if (cmd != NULL && *cmd != '\0') {
                        argc = 1;
                        argv = (char **)&cmd;
                } else {
                        argc = 0;
                        argv = NULL;
                }
        } else {
                argc = sc->argc;
                argv = sc->argv;
        }
        if (cwd != NULL) {
                free(new_wp->cwd);
                new_wp->cwd = cwd;
        }

        /*
         * Replace the stored arguments if there are new ones. If not, the
         * existing ones will be used (they will only exist for respawn).
         */
        if (argc > 0) {
                cmd_free_argv(new_wp->argc, new_wp->argv);
                new_wp->argc = argc;
                new_wp->argv = cmd_copy_argv(argc, argv);
        }

        /* Create an environment for this pane. */
        child = environ_for_session(s, 0);
        if (sc->environ != NULL)
                environ_copy(sc->environ, child);
        environ_set(child, "TMUX_PANE", 0, "%%%u", new_wp->id);

        /*
         * Then the PATH environment variable. The session one is replaced from
         * the client if there is one because otherwise running "tmux new
         * myprogram" wouldn't work if myprogram isn't in the session's path.
         */
        if (c != NULL && c->session == NULL) { /* only unattached clients */
                ee = environ_find(c->environ, "PATH");
                if (ee != NULL)
                        environ_set(child, "PATH", 0, "%s", ee->value);
        }
        if (environ_find(child, "PATH") == NULL)
                environ_set(child, "PATH", 0, "%s", _PATH_DEFPATH);

        /* Then the shell. If respawning, use the old one. */
        if (~sc->flags & SPAWN_RESPAWN) {
                tmp = options_get_string(s->options, "default-shell");
                if (!checkshell(tmp))
                        tmp = _PATH_BSHELL;
                free(new_wp->shell);
                new_wp->shell = xstrdup(tmp);
        }
        environ_set(child, "SHELL", 0, "%s", new_wp->shell);

        /* Log the arguments we are going to use. */
        log_debug("%s: shell=%s", __func__, new_wp->shell);
        if (new_wp->argc != 0) {
                cp = cmd_stringify_argv(new_wp->argc, new_wp->argv);
                log_debug("%s: cmd=%s", __func__, cp);
                free(cp);
        }
        log_debug("%s: cwd=%s", __func__, new_wp->cwd);
        cmd_log_argv(new_wp->argc, new_wp->argv, "%s", __func__);
        environ_log(child, "%s: environment ", __func__);

        /* Initialize the window size. */
        memset(&ws, 0, sizeof ws);
        ws.ws_col = screen_size_x(&new_wp->base);
        ws.ws_row = screen_size_y(&new_wp->base);
        ws.ws_xpixel = w->xpixel * ws.ws_col;
        ws.ws_ypixel = w->ypixel * ws.ws_row;

        /* Block signals until fork has completed. */
        sigfillset(&set);
        sigprocmask(SIG_BLOCK, &set, &oldset);

        /* If the command is empty, don't fork a child process. */
        if (sc->flags & SPAWN_EMPTY) {
                new_wp->flags |= PANE_EMPTY;
                new_wp->base.mode &= ~MODE_CURSOR;
                new_wp->base.mode |= MODE_CRLF;
                goto complete;
        }
        new_wp->flags &= ~PANE_EMPTY;

        /* Store current working directory and change to new one. */
        if (getcwd(path, sizeof path) != NULL) {
                if (chdir(new_wp->cwd) == 0)
                        actual_cwd = new_wp->cwd;
                else if (home != NULL && chdir(home) == 0)
                        actual_cwd = home;
                else if (chdir("/") == 0)
                        actual_cwd = "/";
        }

        /* Fork the new process. */
        new_wp->pid = fdforkpty(ptm_fd, &new_wp->fd, new_wp->tty, NULL, &ws);
        if (new_wp->pid == -1) {
                xasprintf(cause, "fork failed: %s", strerror(errno));
                new_wp->fd = -1;
                if (~sc->flags & SPAWN_RESPAWN) {
                        server_client_remove_pane(new_wp);
                        layout_close_pane(new_wp);
                        window_remove_pane(w, new_wp);
                }
                sigprocmask(SIG_SETMASK, &oldset, NULL);
                environ_free(child);
                return (NULL);
        }

        /*
         * In the parent process, everything is done now. Change the working
         * directory back.
         */
        if (new_wp->pid != 0) {
                if (actual_cwd != NULL &&
                    chdir(path) != 0 &&
                    (home == NULL || chdir(home) != 0))
                        chdir("/");
                goto complete;
        }

        /*
         * Child process. Set PWD to the working directory.
         */
        if (actual_cwd != NULL)
                environ_set(child, "PWD", 0, "%s", actual_cwd);

        /*
         * Update terminal escape characters from the session if available and
         * force VERASE to tmux's backspace.
         */
        if (tcgetattr(STDIN_FILENO, &now) != 0)
                _exit(1);
        if (s->tio != NULL)
                memcpy(now.c_cc, s->tio->c_cc, sizeof now.c_cc);
        key = options_get_number(global_options, "backspace");
        if (key >= 0x7f)
                now.c_cc[VERASE] = '\177';
        else
                now.c_cc[VERASE] = key;
        if (tcsetattr(STDIN_FILENO, TCSANOW, &now) != 0)
                _exit(1);

        /* Clean up file descriptors and signals and update the environment. */
        proc_clear_signals(server_proc, 1);
        closefrom(STDERR_FILENO + 1);
        sigprocmask(SIG_SETMASK, &oldset, NULL);
        log_close();
        environ_push(child);

        /*
         * If given multiple arguments, use execvp(). Copy the arguments to
         * ensure they end in a NULL.
         */
        if (new_wp->argc != 0 && new_wp->argc != 1) {
                argvp = cmd_copy_argv(new_wp->argc, new_wp->argv);
                execvp(argvp[0], argvp);
                _exit(1);
        }

        /*
         * If one argument, pass it to $SHELL -c. Otherwise create a login
         * shell.
         */
        cp = strrchr(new_wp->shell, '/');
        if (new_wp->argc == 1) {
                tmp = new_wp->argv[0];
                if (cp != NULL && cp[1] != '\0')
                        xasprintf(&argv0, "%s", cp + 1);
                else
                        xasprintf(&argv0, "%s", new_wp->shell);
                execl(new_wp->shell, argv0, "-c", tmp, (char *)NULL);
                _exit(1);
        }
        if (cp != NULL && cp[1] != '\0')
                xasprintf(&argv0, "-%s", cp + 1);
        else
                xasprintf(&argv0, "-%s", new_wp->shell);
        execl(new_wp->shell, argv0, (char *)NULL);
        _exit(1);

complete:
        new_wp->flags &= ~PANE_EXITED;

        sigprocmask(SIG_SETMASK, &oldset, NULL);
        window_pane_set_event(new_wp);
        environ_free(child);
        spawn_fire_pane_created(sc, new_wp);

        if (sc->flags & SPAWN_RESPAWN)
                return (new_wp);
        if (sc->flags & SPAWN_MODAL) {
                w->modal_last = w->active;
                w->modal = new_wp;
                window_redraw_active_switch(w, new_wp);
                if (sc->flags & SPAWN_NONOTIFY)
                        window_set_active_pane(w, new_wp, 0);
                else
                        window_set_active_pane(w, new_wp, 1);
        } else if (((~sc->flags & SPAWN_DETACHED) || w->active == NULL) &&
            w->modal == NULL) {
                if (sc->flags & SPAWN_NONOTIFY)
                        window_set_active_pane(w, new_wp, 0);
                else
                        window_set_active_pane(w, new_wp, 1);
        }
        if (~sc->flags & SPAWN_NONOTIFY)
                events_fire_window("window-layout-changed", w);
        return (new_wp);
}

struct spawn_editor_state {
        char                    *path;
        pid_t                    pid;
        spawn_finish_edit_cb     cb;
        void                    *arg;
};

static void
spawn_editor_free(struct spawn_editor_state *es)
{
        unlink(es->path);
        free(es->path);
        free(es);
}

void
spawn_cancel_editor(struct spawn_editor_state *es)
{
        if (es == NULL)
                return;
        es->cb = NULL;
        es->arg = NULL;
}

pid_t
spawn_get_editor_pid(struct spawn_editor_state *es)
{
        if (es == NULL)
                return (-1);
        return (es->pid);
}

void
spawn_editor_finish(struct window_pane *wp)
{
        struct spawn_editor_state       *es = wp->editor;
        FILE                            *f;
        char                            *buf = NULL;
        off_t                            len = 0;
        int                              status = 128 + SIGHUP;

        if (es == NULL)
                return;
        wp->editor = NULL;

        if (wp->flags & PANE_STATUSREADY) {
                if (WIFEXITED(wp->status))
                        status = WEXITSTATUS(wp->status);
                else if (WIFSIGNALED(wp->status))
                        status = WTERMSIG(wp->status) + 128;
        }

        if (es->cb == NULL) {
                spawn_editor_free(es);
                return;
        }
        if (status != 0) {
                es->cb(NULL, 0, es->arg);
                spawn_editor_free(es);
                return;
        }

        f = fopen(es->path, "r");
        if (f != NULL) {
                if (fseeko(f, 0, SEEK_END) == 0) {
                        len = ftello(f);
                        if (len > 0 && (uintmax_t)len <= (uintmax_t)SIZE_MAX) {
                                if (fseeko(f, 0, SEEK_SET) == 0) {
                                        buf = malloc(len);
                                        if (buf != NULL &&
                                            fread(buf, len, 1, f) != 1) {
                                                free(buf);
                                                buf = NULL;
                                                len = 0;
                                        }
                                }
                        } else
                                len = 0;
                }
                fclose(f);
        }

        es->cb(buf, len, es->arg);
        spawn_editor_free(es);
}

struct spawn_editor_state *
spawn_editor(struct client *c, const char *buf, size_t len,
    spawn_finish_edit_cb cb, void *arg)
{
        struct spawn_editor_state       *es;
        struct spawn_context             sc = { 0 };
        struct session                  *s = c->session;
        struct winlink                  *wl = s->curw;
        struct window                   *w = wl->window;
        struct window_pane              *wp;
        struct layout_cell              *lc;
        struct layout_geometry           lg;
        struct environ                  *env;
        FILE                            *f;
        char                            *cmd, *cause = NULL;
        char                             path[] = _PATH_TMP "tmux.XXXXXXXX";
        const char                      *editor;
        int                              fd;

        if (w->modal != NULL)
                return (NULL);

        editor = options_get_string(global_options, "editor");
        fd = mkstemp(path);
        if (fd == -1)
                return (NULL);
        f = fdopen(fd, "w");
        if (f == NULL) {
                close(fd);
                unlink(path);
                return (NULL);
        }
        if (fwrite(buf, len, 1, f) != 1) {
                fclose(f);
                unlink(path);
                return (NULL);
        }
        fclose(f);

        es = xcalloc(1, sizeof *es);
        es->path = xstrdup(path);
        es->cb = cb;
        es->arg = arg;

        lg.sx = w->sx * 9 / 10;
        lg.sy = w->sy * 9 / 10;
        lg.xoff = w->sx / 2 - lg.sx / 2;
        lg.yoff = w->sy / 2 - lg.sy / 2;
        window_push_modal_zoom(w);
        lc = layout_floating_pane(w, NULL, &lg);
        if (lc == NULL) {
                window_pop_modal_zoom(w);
                spawn_editor_free(es);
                return (NULL);
        }

        xasprintf(&cmd, "%s %s", editor, path);
        env = environ_create();
        sc.s = s;
        sc.wl = wl;
        sc.tc = c;
        sc.wp0 = w->active;
        sc.lc = lc;
        sc.argc = 1;
        sc.argv = &cmd;
        sc.environ = env;
        sc.idx = -1;
        sc.cwd = _PATH_TMP;
        sc.flags = SPAWN_FLOATING|SPAWN_MODAL;

        wp = spawn_pane(&sc, &cause);
        free(cmd);
        environ_free(env);
        if (wp == NULL) {
                free(cause);
                window_pop_modal_zoom(w);
                spawn_editor_free(es);
                return (NULL);
        }
        options_set_number(wp->options, "remain-on-exit", 0);
        es->pid = wp->pid;
        wp->editor = es;
        return (es);
}