Solved

Posting a form without changing the current HTML page.

Posted on 1997-07-10
2
172 Views
Last Modified: 2013-12-25
My Perl script executes UNIX shell commands by system(), exec() or open(). The browser always shows the result of the commands. Can I do something to "cover" this result (by printing a HTML) or simply do not return data to the browser (the page doesn't change in the browser)?
0
Comment
Question by:kenysc
2 Comments
 
LVL 3

Accepted Solution

by:
pc012197 earned 100 total points
ID: 1829028
The unix shell commands print their output to stdout and stderr. The server takes that output and includes it into the page created by the script.
The solution to your problem is to redefine stdout and stderr before invoking the shell commands:

open(SAVEOUT, ">&STDOUT");
open(SAVEERR, ">&STDERR");
open(STDOUT, ">foo.out") || die "Can't redirect stdout";
open(STDERR, ">&STDOUT") || die "Can't dup stdout";

# your unix commands go here...

close(STDOUT);
close(STDERR);

open(STDOUT, ">&SAVEOUT");
open(STDERR, ">&SAVEERR");

See also the perlfunc manpage for the open() function.

0
 
LVL 84

Expert Comment

by:ozo
ID: 1829029
You can also grab the STDOUT of commands with
      $outputfromcommand = `command`;
instead of
      $exitvalueofcommand = system("command");

See the perlop manpage for the qx operator
(or if you really want to cover it in HTML, I suppose you could
wrap it in an HTML comment...)


0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Introduction:   Welcome to my first article ever. To begin with, the reason I write this article.  I participated in a question on Experts Exchange about the start command in Windows and there were some discussion about the usage. The discussio…
I hope you'll find this tutorial useful and interesting. So let's try to extend Tcl with a new package.  For anyone more deeply interested please check out the book "Practical Programming in Tcl and Tk". It's really one of the best written books abo…
Learn the basics of while and for loops in Python.  while loops are used for testing while, or until, a condition is met: The structure of a while loop is as follows:     while <condition>:         do something         repeate: The break statement m…
This tutorial will teach you the core code needed to finalize the addition of a watermark to your image. The viewer will use a small PHP class to learn and create a watermark.

895 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

16 Experts available now in Live!

Get 1:1 Help Now