From 4f131005cbe8b590ce5a8dbbcc358378f173eadb Mon Sep 17 00:00:00 2001
From: Ole Tange <ole@tange.dk>
Date: Fri, 6 Nov 2020 09:48:29 +0100
Subject: [PATCH] plotpipe: --nox = first column is not x-axis.

---
 plotpipe/plotpipe | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/plotpipe/plotpipe b/plotpipe/plotpipe
index 18da3c3..79556c9 100755
--- a/plotpipe/plotpipe
+++ b/plotpipe/plotpipe
@@ -9,7 +9,7 @@ plotpipe - Plot CSV data from a pipe
 
 =head1 SYNOPSIS
 
-I<datagenerator> | B<plotpipe> [-H] [-0] [-C str] [-h] [-V]
+I<datagenerator> | B<plotpipe> [-n] [-H] [-0] [-C str] [-h] [-V]
 
 
 =head1 DESCRIPTION
@@ -48,6 +48,14 @@ B<--header>.
 Show help.
 
 
+=item B<--nox>
+
+=item B<-n>
+
+No x-value. In a multi-column input the first value will normally be
+used as x-value. B<--nox> will use line number as x-value.
+
+
 =item B<--null>
 
 =item B<-0>
@@ -153,6 +161,7 @@ sub options_hash() {
 	 "colsep|col-sep|C=s" => \$opt::colsep,
 	 "help|h" => \$opt::help,
 	 "null|0" => \$opt::null,
+	 "nox|n" => \$opt::nox,
 	 "header|H" => \$opt::header,
 	);
 }
@@ -327,23 +336,22 @@ $ENV{'TMPDIR'} ||= "/tmp";
 my($filehandle,$filename) =
     tempfile(DIR=>$ENV{'TMPDIR'}, TEMPLATE => 'plotXXXXX');
 my $ncols = split /$opt::colsep/, $csv[0];
-if($ncols >= 2) {
+if($ncols >= 2 and not $opt::nox) {
     # Column 1 = x-axis
     for(@csv) {
 	chomp;
 	print $filehandle ((join "\001", split /$opt::colsep/, $_),"\n");
     }
 } else {
-    # Column 1 = y-axis
-    my $t = 1;
-    # Convert 1 column to 2 column
+    # All data = y-axis, invent x-axis
+    my $x = 1;
     for(@csv) {
 	chomp;
-	print $filehandle ((join "\001", $t++, $_),"\n");
+	print $filehandle ((join "\001", $x++, split /$opt::colsep/, $_),"\n");
     }
-    # Plot 2 columns
-unshift(@header,"");
-    $ncols = 2;
+    # Prepend dummy header for x-axis
+    unshift(@header,"");
+    $ncols += 1;
 }
 
 # Generate the variant part of Gnuplot script
@@ -367,7 +375,13 @@ set datafile separator "\001";
 plot @plotscript
 _EOS
 
-open GNUPLOT,"|-", "gnuplot -p -e ".Q($plotscript) or die;
-#print "gnuplot -p -e ".($plotscript);
-close GNUPLOT;
-unlink $filename;
+if(fork) {
+    open GNUPLOT,"|-", "gnuplot -p -e ".Q($plotscript) or die;
+    #print "gnuplot -p -e ".($plotscript);
+    close GNUPLOT;
+    unlink $filename;
+} else {
+    # If script dies unexpectedly, remove the file after 5 sec
+    sleep(5);
+    unlink $filename;
+}