UNIX for Dummies Questions & Answers

myscript.sh inputfilename > /path/to/outfilefilename

#! /usr/bin/perl

my $file = "path/inputfile";
my $outfile = "path/outfile";

if( open(IFILE, "<", "$file") )
{
    if ( open(OFILE, ">", "$outfile") )
    {
        while(my $line = <IFILE> )
        {
            chomp($line);

            ## do your changes
            print OFILE "$line\n"; ## print (or write) to the outfile since we use OFILE( this refers outfile)#
        }
    }
    else
    {
        print "Error: Unable to open file $outfile\n";
    }
}
else
{
    print "Error: Unable to open file $file\n";
}

if ( open(IFILE, "<$file") )

select(OFILE);
print "Welcome\n"; ##It will write in outfile
print "Hai\n";  ##It will write in outfile 
## Please check that i have not use File Handle but still it will write to the outfile bcos we have selected the default output stream.

select(STDOUT);
print "Welcome\n"; # It will print in STDOUT