Index: trunk/src/hid.h
===================================================================
--- trunk/src/hid.h	(revision 13550)
+++ trunk/src/hid.h	(revision 13551)
@@ -355,11 +355,13 @@
 	/* Causes func_ to be called when some condition occurs on the file
 	   descriptor passed. Conditions include data for reading, writing,
 	   hangup, and errors. user_data_ can be anything, it's just passed
-	   to func. */
+	   to func. If the watch function returns pcb_true, the watch is kept, else
+	   it is removed. */
 	  pcb_hidval_t(*watch_file) (int fd_, unsigned int condition_,
-												 void (*func_) (pcb_hidval_t watch_, int fd_, unsigned int condition_, pcb_hidval_t user_data_),
+												 pcb_bool (*func_) (pcb_hidval_t watch_, int fd_, unsigned int condition_, pcb_hidval_t user_data_),
 												 pcb_hidval_t user_data);
-	/* Use this to stop a file watch. */
+
+	/* Use this to stop a file watch; must not be called from within a GUI callback! */
 	void (*unwatch_file) (pcb_hidval_t watch_);
 
 	/* Causes func_ to be called in the mainloop prior to blocking */
Index: trunk/src_plugins/extedit/extedit.c
===================================================================
--- trunk/src_plugins/extedit/extedit.c	(revision 13550)
+++ trunk/src_plugins/extedit/extedit.c	(revision 13551)
@@ -82,7 +82,7 @@
 	pcb_hidval_t wid;
 } extedit_wait_t;
 
-void extedit_fd_watch(pcb_hidval_t watch, int fd, unsigned int condition, pcb_hidval_t user_data)
+pcb_bool extedit_fd_watch(pcb_hidval_t watch, int fd, unsigned int condition, pcb_hidval_t user_data)
 {
 	char tmp[128];
 	int res;
@@ -90,13 +90,15 @@
 
 	/* excess callbacks */
 	if (!ctx->stay)
-		return;
+		return pcb_true;
 
 	res = fread(tmp, 1, sizeof(tmp), ctx->fc);
 	if (res <= 0) {
 		pcb_gui->unwatch_file(ctx->wid);
 		ctx->stay = 0;
+		return pcb_false;
 	}
+	return pcb_true;
 }
 
 /* Invoke the child process, display a "progress bar" or some other indication
Index: trunk/src_plugins/hid_lesstif/main.c
===================================================================
--- trunk/src_plugins/hid_lesstif/main.c	(revision 13550)
+++ trunk/src_plugins/hid_lesstif/main.c	(revision 13551)
@@ -3308,7 +3308,7 @@
 
 
 typedef struct {
-	void (*func) (pcb_hidval_t, int, unsigned int, pcb_hidval_t);
+	pcb_bool (*func) (pcb_hidval_t, int, unsigned int, pcb_hidval_t);
 	pcb_hidval_t user_data;
 	int fd;
 	XtInputId id;
@@ -3340,8 +3340,8 @@
 		pcb_condition |= PCB_WATCH_HANGUP;
 
 	x.ptr = (void *) watch;
-	watch->func(x, watch->fd, pcb_condition, watch->user_data);
-
+	if (!watch->func(x, watch->fd, pcb_condition, watch->user_data))
+		lesstif_unwatch_file(x);
 	return;
 }
 
Index: trunk/src_plugins/lib_gtk_common/util_watch.c
===================================================================
--- trunk/src_plugins/lib_gtk_common/util_watch.c	(revision 13550)
+++ trunk/src_plugins/lib_gtk_common/util_watch.c	(revision 13551)
@@ -27,7 +27,7 @@
 #include "conf_core.h"
 
 typedef struct {
-	void (*func) (pcb_hidval_t, int, unsigned int, pcb_hidval_t);
+	pcb_bool (*func) (pcb_hidval_t, int, unsigned int, pcb_hidval_t);
 	pcb_hidval_t user_data;
 	int fd;
 	GIOChannel *channel;
@@ -42,6 +42,7 @@
 	unsigned int pcb_condition = 0;
 	pcb_hidval_t x;
 	GuiWatch *watch = (GuiWatch *) data;
+	pcb_bool res;
 
 	if (condition & G_IO_IN)
 		pcb_condition |= PCB_WATCH_READABLE;
@@ -53,11 +54,11 @@
 		pcb_condition |= PCB_WATCH_HANGUP;
 
 	x.ptr = (void *) watch;
-	watch->func(x, watch->fd, pcb_condition, watch->user_data);
+	res = watch->func(x, watch->fd, pcb_condition, watch->user_data);
 
 	watch->com->mode_cursor_main(-1);
 
-	return TRUE;									/* Leave watch on */
+	return res;
 }
 
 pcb_hidval_t pcb_gtk_watch_file(pcb_gtk_common_t *com, int fd, unsigned int condition,