[prev in list] [next in list] [prev in thread] [next in thread] 

List:       gnuplot-info-beta
Subject:    Re: Command line way to prevent unbuffered?
From:       Jim Kleckner <jek-gp () kleckner ! net>
Date:       2008-06-30 20:01:13
Message-ID: 48693B89.8020901 () kleckner ! net
[Download RAW message or body]

Ethan Merritt wrote:
> On Monday 10 January 2005 10:46 pm, Ethan Merritt wrote:
>>> diff -u -r1.72 plot.c
>>> --- plot.c    25 Aug 2004 22:33:16 -0000    1.72
>>> +++ plot.c    11 Jan 2005 05:26:21 -0000
>>> @@ -422,7 +422,9 @@
>>>       * Do any non-X platforms suffer from the same problem?
>>>       * EAM - Jan 2004.
>>>       */
>>> -    setvbuf(stdin, (char *) NULL, _IONBF, 0);
>>> +    if (isatty(fileno(stdin))) {
>>> +        setvbuf(stdin, (char *) NULL, _IONBF, 0);
>>> +    }
>>>  #endif
>>
>> I see why you want this.  But speed is no good if the program
>> does not function properly, and previous experience showed that
>> unbuffering the input stream was needed for at least some 
>> implementations of piped input.
> 
> I have changed my mind.  The behavior is not likely to differ
> from user to user, only from one platform to another. So it should
> be a configuration option for building on that platform, not a
> run-time option on the command line.
> 
> How about we wrap the code as follows:
> 
> #ifndef UNBUFFERED_STDIN
>     setvbuf(stdin, (char *) NULL, _IONBF, 0);
> #endif
> 
> and you can provide a brief set of instructions for how to set
> this conditional compilation flag during the cygwin configuration setup.
> I have not used cygwin, so I don't know exactly how that is done.
> 
> It would be nice if you also checked that this doesn't interfere
> with correct execution of "pause" commands, however, since as I
> recall that was one of the original problems this was supposed to fix.
> For instance, please check that "mousevariables.dem" works properly with 
> buffered input under cygwin. 


The attached patch achieves the speedup and works
properly with mousevariables.dem.

The use of __CYGWIN__ makes it specific to that platform.

I suspect this would also help other platforms.

Please consider for upstream inclusion.

Thanks - Jim


["gnuplot-setvbuf.patch" (text/plain)]

diff -urN -x CYGWIN-PATCHES -x 'aclocal.m4*' -x autom4te.cache -x config.cache -x \
config.log -x config.status -x config.h -x config.h.in -x ABOUT-NLS -x Makefile.in.in \
-x Makevars.template -x '*SlackBuild*' -x '*.egg-info' -x '*.class' -x '*.pyc' -x \
'*.mo' -x '*.gmo' -x '*.orig' -x '*.rej' -x '*.spec' -x '*.temp' -x '*~' -x \
'*.stackdump' -x COPYING -x INSTALL -x compile -x config-ml.in -x config.guess -x \
config.sub -x depcomp -x elisp-comp -x install-sh -x ltmain.sh -x mdate-sh -x missing \
-x mkinstalldirs -x py-compile -x symlink-tree -x texinfo.tex -x ylwrap -x \
config.rpath -x Makefile.in -x makefile.in -x configure -x omf.make -x xmldocs.make \
-x gnome-doc-utils.make -x gnome-doc-utils.m4 -x intltool.m4 -x intltool-extract -x \
intltool-extract.in -x intltool-merge -x intltool-merge.in -x intltool-update -x \
intltool-update.in -x gnuplot.texi origsrc/gnuplot-4.2.3/src/plot.c \
                src/gnuplot-4.2.3/src/plot.c
--- origsrc/gnuplot-4.2.3/src/plot.c	2007-06-07 09:26:32.000000000 -0700
+++ src/gnuplot-4.2.3/src/plot.c	2008-06-27 17:45:33.974729600 -0700
@@ -433,8 +433,15 @@
      * Failing this, I propose we just make the call and
      * ignore the return : its probably not a big deal
      */
+#ifdef __CYGWIN__
+    if (isatty(fileno(stdin))) {
+        if (setvbuf(stdout, (char *) NULL, _IOLBF, (size_t) 1024) != 0)
+            (void) fputs("Could not linebuffer stdout\n", stderr);
+    }
+#else
     if (setvbuf(stdout, (char *) NULL, _IOLBF, (size_t) 1024) != 0)
 	(void) fputs("Could not linebuffer stdout\n", stderr);
+#endif
 
 #ifdef X11
     /* This call used to be in x11.trm, with the following comment:
@@ -448,8 +455,14 @@
      * Do any non-X platforms suffer from the same problem?
      * EAM - Jan 2004.
      */
+#ifdef __CYGWIN__
+    if (isatty(fileno(stdin))) {
+        setvbuf(stdin, (char *) NULL, _IONBF, 0);
+    }
+#else
     setvbuf(stdin, (char *) NULL, _IONBF, 0);
 #endif
+#endif
 
 #endif
 
diff -urN -x CYGWIN-PATCHES -x 'aclocal.m4*' -x autom4te.cache -x config.cache -x \
config.log -x config.status -x config.h -x config.h.in -x ABOUT-NLS -x Makefile.in.in \
-x Makevars.template -x '*SlackBuild*' -x '*.egg-info' -x '*.class' -x '*.pyc' -x \
'*.mo' -x '*.gmo' -x '*.orig' -x '*.rej' -x '*.spec' -x '*.temp' -x '*~' -x \
'*.stackdump' -x COPYING -x INSTALL -x compile -x config-ml.in -x config.guess -x \
config.sub -x depcomp -x elisp-comp -x install-sh -x ltmain.sh -x mdate-sh -x missing \
-x mkinstalldirs -x py-compile -x symlink-tree -x texinfo.tex -x ylwrap -x \
config.rpath -x Makefile.in -x makefile.in -x configure -x omf.make -x xmldocs.make \
-x gnome-doc-utils.make -x gnome-doc-utils.m4 -x intltool.m4 -x intltool-extract -x \
intltool-extract.in -x intltool-merge -x intltool-merge.in -x intltool-update -x \
intltool-update.in -x gnuplot.texi origsrc/gnuplot-4.2.3/src/readline.c \
                src/gnuplot-4.2.3/src/readline.c
--- origsrc/gnuplot-4.2.3/src/readline.c	2006-04-28 09:54:03.000000000 -0700
+++ src/gnuplot-4.2.3/src/readline.c	2008-06-27 17:45:35.476889600 -0700
@@ -1014,7 +1014,13 @@
 #   endif			/* TERMIOS */
 #  endif			/* not SGTTY */
 # else				/* OSK */
+#ifdef __CYGWIN__
+        if (isatty(fileno(stdin))) {
+            setbuf(stdin, (char *) 0);	/* Make stdin and stdout unbuffered */
+        }
+#else
 	setbuf(stdin, (char *) 0);	/* Make stdin and stdout unbuffered */
+#endif
 	setbuf(stderr, (char *) 0);
 	_gs_opt(STDIN, &new_settings);
 # endif				/* OSK */



-------------------------------------------------------------------------
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://sourceforge.net/services/buy/index.php

_______________________________________________
gnuplot-beta mailing list
gnuplot-beta@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/gnuplot-beta


[prev in list] [next in list] [prev in thread] [next in thread]