Allow "-L 0" to be propagated with "-R" so that a remote process can have its rate limiting turned off as well as on; and update the manual to note this (#193).

docs/pv.1

@@ -267,6 +267,9 @@ If the file already exists, it will be truncated.
 .BI \-L\  RATE \fR,\ \fB\-\-rate-limit\  RATE
 Limit the transfer to a maximum of \fIRATE\fR bytes per second.
 The same suffixes as \*(lq\fB\-\-size\fR\*(rq can be used.
+Decimal values are allowed.
+Specifying 0 will turn off rate limiting, which is useful with
+\*(lq\fB\-\-remote\fR\*(rq.
 .TP
 .BI \-B\  BYTES \fR,\ \fB\-\-buffer-size\  BYTES
 Use a transfer buffer size of \fIBYTES\fR bytes.

docs/pv.1.md

@@ -276,7 +276,9 @@ are explicitly switched on will be shown.
 **-L RATE, \--rate-limit RATE**
 
 :   Limit the transfer to a maximum of *RATE* bytes per second. The same
-    suffixes as "**\--size**" can be used.
+    suffixes as "**\--size**" can be used. Decimal values are allowed.
+    Specifying 0 will turn off rate limiting, which is useful with
+    "**\--remote**".
 
 **-B BYTES, \--buffer-size BYTES**
 

src/include/options.h

@@ -114,7 +114,8 @@ struct opts_s {
 	bool show_stats;	       /* set to write statistics at the end */
 	bool width_set_manually;       /* width was set manually, not detected */
 	bool height_set_manually;      /* height was set manually, not detected */
-	bool rate_limit_active;	       /* whether a rate limit was set */
+	bool rate_limit_specified;     /* whether a rate limit value was given */
+	bool rate_limit_active;	       /* whether rate limiting is in effect (>0) */
 };
 
 /*@-exportlocal@*/

src/include/pv-internal.h

@@ -237,7 +237,8 @@ struct pvstate_s {
 		bool show_stats;		 /* show statistics on exit */
 		bool width_set_manually;	 /* width was set manually, not detected */
 		bool height_set_manually;	 /* height was set manually, not detected */
-		bool rate_limit_active;		 /* whether a rate limit is in effect */
+		bool rate_limit_specified;	 /* whether a rate limit value was given */
+		bool rate_limit_active;		 /* whether a rate limit is in effect (>0) */
 	} control;
 
 	/*******************

src/include/pv.h

@@ -266,7 +266,7 @@ extern void pv_state_stop_at_size_set(pvstate_t, bool);
 extern void pv_state_sync_after_write_set(pvstate_t, bool);
 extern void pv_state_direct_io_set(pvstate_t, bool);
 extern void pv_state_sparse_output_set(pvstate_t, bool);
-extern void pv_state_rate_limit_set(pvstate_t, long double, bool);
+extern void pv_state_rate_limit_set(pvstate_t, long double, bool, bool);
 extern void pv_state_target_buffer_size_set(pvstate_t, size_t);
 extern void pv_state_no_splice_set(pvstate_t, bool);
 extern void pv_state_pipe_buffer_size_set(pvstate_t, size_t);

src/main/main.c

@@ -903,7 +903,7 @@ int main(int argc, char **argv)
 	pv_state_sync_after_write_set(state, opts->sync_after_write);
 	pv_state_direct_io_set(state, opts->direct_io);
 	pv_state_discard_input_set(state, opts->discard_input);
-	pv_state_rate_limit_set(state, opts->rate_limit, opts->rate_limit_active);
+	pv_state_rate_limit_set(state, opts->rate_limit, opts->rate_limit_specified, opts->rate_limit_active);
 	pv_state_target_buffer_size_set(state, opts->buffer_size);
 	pv_state_no_splice_set(state, opts->no_splice);
 	pv_state_pipe_buffer_size_set(state, opts->pipe_buffer_size);

src/main/options.c

@@ -801,6 +801,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 
 	opts->width_set_manually = false;
 	opts->height_set_manually = false;
+	opts->rate_limit_specified = false;
 
 	do {
 #ifdef HAVE_GETOPT_LONG
@@ -1058,6 +1059,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 			break;
 		case 'L':
 			(void) pv_getnum_size(optarg, opts->decimal_units, &(opts->rate_limit));
+			opts->rate_limit_specified = true;
 #if HAVE_MATH_H
 			/*@-unrecog@ *//* splint doesn't know nextafterl(). */
 			if (opts->rate_limit < nextafterl(0, INFINITY)) {

src/pv/remote.c

@@ -42,7 +42,8 @@ struct remote_msg {
 	unsigned int height;		 /* screen height */
 	bool width_set_manually;	 /* width was set manually, not detected */
 	bool height_set_manually;	 /* height was set manually, not detected */
-	bool rate_limit_active;		 /* whether rate limiting is in effect */
+	bool rate_limit_specified;	 /* whether a rate limit value was set */
+	bool rate_limit_active;		 /* whether rate limiting is in effect (>0) */
 	char name[256];			 /* flawfinder: ignore */
 	char format[256];		 /* flawfinder: ignore */
 	char extra_display[256];	 /* flawfinder: ignore */
@@ -107,6 +108,7 @@ int pv_remote_set(pvstate_t state, pid_t remote)
 	msgbuf.bufpercent = state->control.format_option.bufpercent;
 	msgbuf.lastwritten = state->control.format_option.lastwritten;
 	msgbuf.rate_limit = state->control.rate_limit;
+	msgbuf.rate_limit_specified = state->control.rate_limit_specified;
 	msgbuf.rate_limit_active = state->control.rate_limit_active;
 	msgbuf.buffer_size = state->control.target_buffer_size;
 	msgbuf.size = state->control.size;
@@ -324,8 +326,9 @@ static bool pv__rxsignal_usr2(pvstate_t state)
 
 	pv_state_set_format_options(state, format_options);
 
-	if (msgbuf.rate_limit_active)
-		pv_state_rate_limit_set(state, msgbuf.rate_limit, msgbuf.rate_limit_active);
+	if (msgbuf.rate_limit_specified)
+		pv_state_rate_limit_set(state, msgbuf.rate_limit, msgbuf.rate_limit_specified,
+					msgbuf.rate_limit_active);
 	if (msgbuf.buffer_size > 0) {
 		pv_state_target_buffer_size_set(state, msgbuf.buffer_size);
 	}

src/pv/state.c

@@ -649,9 +649,18 @@ void pv_state_discard_input_set(pvstate_t state, bool val)
 	state->control.discard_input = val;
 }
 
-void pv_state_rate_limit_set(pvstate_t state, long double val, bool is_active)
+/*
+ * If "was_specified" is true, the limit was specified on the command line.
+ * This is used with --remote to determine whether to affect the remote
+ * process's rate limit settings.
+ *
+ * if "is_active" is true, the limit ("val") is not zero so rate limiting is
+ * active.
+ */
+void pv_state_rate_limit_set(pvstate_t state, long double val, bool was_specified, bool is_active)
 {
 	state->control.rate_limit = val;
+	state->control.rate_limit_specified = was_specified;
 	state->control.rate_limit_active = is_active;
 }