(mgp-users 00120) stupid locale/gs interaction...

[Fabien COELHO <coelho@cri.ensmp.fr>]

Hi,

I could not display postscript files with mgp, so I investigated the bug.

After a few hours of investigation, I finally found a pretty !"£$%^&*
problem, which is due to the locale feature. Indeed, I compiled with
--enable-locale, and I have LANG=fr in my environment, so that French word
boundaries are understood properly by mgp. When it comes to translating a
postscript file, mgp forks/execs a gs and pipes commands to it, including
a scale, which is output as:

	3,040000 2,000000 scale

instead of 

	3.040000 2.000000 scale

because in French a comma is used for separating the fractional part of
floating point numbers. However, it happends that the gs parser is not
aware of French conventions;-)

I appended a patch to fix this problem, but it is not really beautiful.
I have not found how to specify the separator in a format.
Thanks for considering it or a similar fix to this problem...

Have a nice day,

Fabien.

--- draw.c.orig	Mon Mar  8 16:42:06 1999
+++ draw.c	Wed Mar 10 10:02:18 1999
@@ -120,6 +120,8 @@
 		return 1;
 	if (3 < p - p0 && strcasecmp(p - 3, ".ps") == 0)
 		return 1;
+	if (6 < p - p0 && strcasecmp(p - 6, ".idraw") == 0)
+		return 1;
 	return 0;
 }
 
@@ -3244,6 +3246,18 @@
 	x_registerseed(state, NULL, NULL);
 }
 
+/* print double d to fd with a *dot*
+ * so as to avoid interaction with the locale setting.
+ */
+static void fprint_fdot(FILE * fd, double d)
+{
+  char buffer[32], * comma;
+  sprintf(buffer, "%f", d);
+  comma = strchr(buffer, ',');
+  if (comma) *comma = '.';
+  fprintf(fd, "%s", buffer);
+}
+
 static char *
 epstoimage(state, epsfile, x, y, width, height, xzoom, yzoom)
 	struct render_state *state;
@@ -3422,8 +3436,10 @@
 	}
 	sigpipe_handler = signal(SIGPIPE, SIG_IGN);	/* XXX: avoid SIGPIPE */
 	pfd[0][1] = -1;
-	fprintf(fp, "%f %f scale\n", (double)xzoom/100., (double)yzoom/100.);
-	fprintf(fp, "%d %d translate\n", -1 * x, -1 * y);
+	fprint_fdot(fp, (double)xzoom/100.);
+	fprintf(fp, " ");
+	fprint_fdot(fp, (double)yzoom/100.);
+	fprintf(fp, " scale\n%d %d translate\n", -1 * x, -1 * y);
 	fprintf(fp, "(%s) run\n", epsfile);
 	fprintf(fp, "showpage\n");
 	fprintf(fp, "quit\n");