I have a script which has been working fine until last week and i dont know why. 
$graph .= <<BLOCK;
set terminal png transparent
set output "tmp/$random.png"
set size 0.9,0.5
set pointsize 0
set xdata time
set format x "%a\\n%H:00"
set ylabel "Degrees C"
set xlabel "Hours"
set timefmt "%Y-%m-%d%H:%M:%S"
set key below
plot\\
BLOCK

foreach $i (@inputs){

$graph = $graph . "\"tmp/$random.dat\" using 1:" . $c . " title '$i' w
+ith lines,\\\n";

$c++;

}

$graph = substr($graph, 0, (length($graph)-3));

open (GNUPLOT, "|/usr/bin/gnuplot") or die $!;
print GNUPLOT $graph . "\n\n";
close (GNUPLOT);

[download]
sample datafile: 
set terminal png transparent
set output "tmp/854.png"
set size 0.9,0.5
set pointsize 0
set xdata time
set format x "%a\n%H:00"
set ylabel "Degrees C"
set xlabel "Hours"
set timefmt "%Y-%m-%d%H:%M:%S"
set key below
plot\
"tmp/854.dat" using 1:2 title 'D4_AVG' with lines

[download]
The datafile is made fine, but no graph image file is produced. When i save $graph to file and then paste it to gnuplot on command line - its works fine. Your help would be great! Dan

In reply to gnuplot problems by danambroseUK

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