The fvwm manual notes the potential for race conditions when using the
Exec command, and I stumbled across this recently when trying to put more
of my X startup under fvwm's control (the xrdb command didn't complete
before xclock started). So I added an ExecWait command for running
programs synchronously. It's OK as it is for short-lived programs, but
for use with longer-lived things it needs support for the EscapeFunc
mechanism.
--- ChangeLog 2002/06/21 05:35:43 1.1847
+++ ChangeLog 2002/06/21 10:16:03
@@ -1,3 +1,13 @@
+2002-06-21 Tony Finch <[EMAIL PROTECTED]>
+
+ * fvwm/builtins.c:
+ * fvwm/commands.h:
+ * fvwm/functable.c:
+ * fvwm/fvwm.1:
+ Add an ExecWait command for running a program in a blocking
+ fashion, in order to avoid race conditions of the kind mentioned
+ in the manual under the Exec command.
+
2002-06-21 olicha <[EMAIL PROTECTED]>
* fvwm/fvwm.1:
--- fvwm/builtins.c 2002/06/19 14:11:27 1.359
+++ fvwm/builtins.c 2002/06/21 10:16:03
@@ -1816,6 +1816,28 @@
return;
}
+void CMD_ExecWait(F_CMD_ARGS)
+{
+ pid_t pid;
+ char *cmd;
+
+ switch (pid = fork())
+ {
+ case -1:
+ fvwm_msg(ERR,"ExecWait","fork failed (%s)",strerror(errno));
+ break;
+ case 0:
+ cmd = safestrdup(action);
+ execl(exec_shell_name, exec_shell_name, "-c", cmd, NULL);
+ fvwm_msg(ERR,"ExecWait","execl failed (%s)",strerror(errno));
+ exit(100);
+ default:
+ waitpid(pid, NULL, 0);
+ break;
+ }
+ return;
+}
+
void CMD_Refresh(F_CMD_ARGS)
{
refresh_window(Scr.Root, True);
--- fvwm/commands.h 2002/06/19 14:11:27 1.21
+++ fvwm/commands.h 2002/06/21 10:16:03
@@ -75,6 +75,7 @@
F_EWMH_NUMBER_OF_DESKTOPS,
F_EXEC,
F_EXEC_SETUP,
+ F_EXEC_WAIT,
F_FAKE_CLICK,
F_FUNCTION,
F_GLOBAL_OPTS,
@@ -265,6 +266,7 @@
void CMD_EwmhNumberOfDesktops(F_CMD_ARGS);
void CMD_Exec(F_CMD_ARGS);
void CMD_ExecUseShell(F_CMD_ARGS);
+void CMD_ExecWait(F_CMD_ARGS);
void CMD_FakeClick(F_CMD_ARGS);
void CMD_FlipFocus(F_CMD_ARGS);
void CMD_Focus(F_CMD_ARGS);
--- fvwm/functable.c 2002/06/19 14:12:45 1.1
+++ fvwm/functable.c 2002/06/21 10:16:03
@@ -125,6 +125,7 @@
F_EWMH_NUMBER_OF_DESKTOPS, 0),
CMD_ENTRY("exec", CMD_Exec, F_EXEC, 0),
CMD_ENTRY("execuseshell", CMD_ExecUseShell, F_EXEC_SETUP, 0),
+ CMD_ENTRY("execwait", CMD_ExecWait, F_EXEC_WAIT, 0),
CMD_ENTRY("fakeclick", CMD_FakeClick, F_FAKE_CLICK, 0),
CMD_ENTRY("flipfocus", CMD_FlipFocus, F_FLIP_FOCUS, FUNC_NEEDS_WINDOW),
CMD_ENTRY("focus", CMD_Focus, F_FOCUS, FUNC_NEEDS_WINDOW),
--- fvwm/fvwm.1 2002/06/21 05:35:44 1.21
+++ fvwm/fvwm.1 2002/06/21 10:16:03
@@ -8145,6 +8145,17 @@
Read /tmp/file
.EE
do not work reliably.
+Use the
+.B ExecWait
+command instead.
+
+.TP
+.BI "ExecWait " command
+Executes
+.IR command
+and waits for it to complete.
+Do not use this for programs that are going to run for any significant
+length of time because fvwm is unresponsive while waiting.
.TP
.BI "ExecUseShell [" shell "]"
Tony.
--
f.a.n.finch <[EMAIL PROTECTED]> http://dotat.at/
SHANNON ROCKALL: SOUTHERLY VEERING WESTERLY 4 OR 5. RAIN OR SHOWERS. MODERATE
OR GOOD.
--
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