Jameson C. Burt wrote:
> Within Perl, I construct programs in other programming languages
> and submit the result to a Unix (Linux or IBM AIX) operating system
> with 2GB to 8GB memory.
> I submit such a program to the operating system using Perl's
> qx()
> Unfortunately, giving qx() over 128,420 characters (about and can vary
> by a few characters) then returns nothing.
> Yet, giving qx() 128,000 characters gets properly executed by the
> operating system.
>
> Following is an example,
> expedited from my original test that actually had 1270 lines.
> Only with fewer lines (eg, replace 1370 by 1269) will this program output
> "Last line of large program!"
> Here's the program that constructs
> and tries giving qx() over 128,000 characters of code:
> #!/usr/bin/perl -w
> $shorty = ' ' x 99 . '#' . "\n" ; #100/101 characters
> #Repeat 1370 lines of $shorty into @manylines:
> # foreach $i (0..1269) {$manylines[$i] = $shorty} ; #Succeeds
> foreach $i (0..1370) {$manylines[$i] = $shorty} ;
> $manylines[$#manylines + 1] = 'echo "Last Line of large program!"' ;
You can simplify that to:
my @manylines = ( ( ' ' x 99 . "#\n" ) x 1371, 'echo "Last Line of large
program!"' );
> print qx(@manylines) ;
> # system(qq(@manylines)) ; #Same problem.
Your line of code is a comment (The # character starts a comment in shell)
which is why nothing is returned:
$ perl -e'
my @manylines = ( ( " " x 99 . "#\n" ) x 1371, q[echo "Last Line of large
program!"] );
print [EMAIL PROTECTED];
' | wc
0 0 0
$ perl -e'
my @manylines = ( ( " " x 99 . "\n" ) x 1371, q[echo "Last Line of large
program!"] );
print [EMAIL PROTECTED];
' | wc
1 5 28
$ perl -e'
my @manylines = ( ( " " x 99 . "\n" ) x 1371, q[echo "Last Line of large
program!"] );
print [EMAIL PROTECTED];
'
Last Line of large program!
> However, appending the following lines to the above code
> will properly execute those 1370 lines.
> open(OUTFILE, ">/tmp/zz.out") ;
> print(OUTFILE @manylines) ;
> close(OUTFILE) ;
> system("bash /tmp/zz.out") ;
> While I can run this latter code, it both adds more code
> and adds a file to the operating system's filesystem.
>
> Can qx() accept large numbers of characters,
> perhaps using some simple technique?
When it is saved as a file the shell (bash) ignores the comment lines.
John
--
Perl isn't a toolbox, but a small machine shop where you can special-order
certain sorts of tools at low cost and in short order. -- Larry Wall
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
http://learn.perl.org/
