I am trying to learn perl, and am trying to implement something simple: reading, updating, then writing an index value to a file. This is what it would be in bash:

index = `cat /tmp/myfile.index`
$index = $index + 1
echo $index > /tmp/myfile.index
exit 0

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This is what I think I need to do in perl (comments about specific lines of code follow the code):

if(! -e "/tmp/test.index") {
  system("/usr/bin/touch /tmp/test.index"); }
#This first test is necessary because if I add the creation permission
+ to the open command, it clobbers the file, preventing me from readin
+g from it
open(FILE, "+</tmp/test.index") || die $!;
$index = <FILE>;
#printing out the value of $index leads me to believe that this part w
+orks

if( ! $index =~ /[0-9]+/ ) {
  $index = 1; }
#This should handle any sort of corruption to the file
$i++;
truncate(FILE, 0);
#I do this to be safe.  But when I do, it prepends two null characters
+.  
print FILE $index;
#This command has no apparent effect.  
close(FILE);
exit 0;

[download]

Help?

In reply to the manuals fail me by Anonymous Monk

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