Contributed by Buckaroo Buddha
on May 10, 2000 at 20:51 UTC
Q&A
> input and output
Description: I wanted to do something like the following.
open( FILE, $file );
redirect( STDOUT, FILE );
Your mission: define sub redirect. :-) Answer: how do i redirect STDOUT, STDIN, or STDERR to a FILE?
contributed by perlmonkey The easist way to do this is to use fdopen from IO::Handle:
use IO::Handle;
open INPUT, '<', "input.txt" or die $!;
open OUTPUT, '>', "output.txt" or die $!;
open ERROR, '>', "error.txt" or die $!;
STDIN->fdopen( \*INPUT, 'r' ) or die $!;
STDOUT->fdopen( \*OUTPUT, 'w' ) or die $!;
STDERR->fdopen( \*ERROR, 'w' ) or die $!;
# prints to output.txt:
print "Hello Output File\n";
# reads everything from input.txt and prints it to output.txt:
print <>;
# prints to error.txt:
warn "Hello Error File\n";
| Answer: how do i redirect STDOUT, STDIN, or STDERR to a FILE?
contributed by plaid The typical way to do this would be in the way
you run it from the command line, e.g.
./script.pl < infile > outfile
This would take STDIN from infile and put STDOUT
to outfile. The sh type shells and csh type
shells have different ways to do STDERROR. Under
bash, you'd do something like
./script.pl < infile > outfile 2> errfile
| Answer: how do i redirect STDOUT, STDIN, or STDERR to a FILE?
contributed by pwesthagen Try this, worked for me:
open FILE, ">$file";
select FILE; # print will use FILE instead of STDOUT
print "Hello, world!"; # goes to FILE
select STDOUT; # back to normal
print "Goodbye."; # goes to STDOUT
|
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