Home Scripting Perl Tutorial Print Output
Main Menu
System Verilog
Open Vera
Digital Concepts
Verification Basics
    - Perl Tutorial
        -- Perl Definition
        -- Syntax & Variables
        -- strings
        -- Arrays
        -- Associative Arrays
        -- If & While Loop
        -- File Input
        -- Print Output
        -- Strings and Regular Expressions
        -- Subroutines
        -- Running External Programs
        -- References
        -- Terse Perl
    - Bash
    - Makefile Tutorial
    - Perl Examples
    - Bash Examples
Interview Questions
Computer Architechture
C and C++
AsicGuru Blog
Tags Cloud
Usefull Sites
Know Your IP/Location
Local Information India
Buy Car/Inverter Batteries
Real Estate India
Sports Accessories India
Perl: Print Output
Share This Articale:

Print Output
Print takes a series of things to print separated by commas. By default, print writes to the STDOUT file handle.

print "Woo Hoo\n";                                         ## print a string to STDOUT
$num = 42;
$str = " Hoo";
print "Woo", $a, " bbb $num", "\n";                ## print several things

An optional first argument to print can specify the destination file handle. There is no comma after the file handle, but I always forget to omit it.

print FILE "Here", " there", " everywhere!", "\n"; ## no comma after FILE

File Processing Example

As an example, here's some code that opens each of the files listed in the @ARGV array, and reads in and prints out their contents to standard output...

#!/usr/bin/perl -w
require 5.004;
## Open each command line file and print its contents to standard out
foreach $fname (@ARGV) {
   open(FILE, $fname) || die("Could not open $fname\n");
   while($line = ) {
      print $line;

The above uses "die" to abort the program if one of the files cannot be opened. We could use a more flexible strategy where we print an error message for that file but continue to try to process the other files. Alternately we could use the function call exit(-1) to exit the program with an error code. Also, the following shift pattern is a common alternative way to iterate through an array...

while($fname = shift(@ARGV)) {...

This Articles is written/submitted by puneet (Puneet Aggarwal). You can also contribute to Asicguru.com. Click here to start

Prev << File Input

Next >> Strings and Regular Expressions

Sign In
Login with :-
| | |  
  • Bookmark