Hello aral,

The ungets method from FileHandle::Unget works on STDIN:

#! perl
use strict;
use warnings;
use FileHandle::Unget;

$| = 1;

my $fh = FileHandle::Unget->new(\*STDIN)
  or die "Cannot open filehandle: $!";

print "\nEnter a string: ";
read($fh, my $buffer1, 10);
print "\nThe first  10 characters: '$buffer1'\n";

$fh->ungets($buffer1);

read($fh, my $buffer2, 15);
print "The \"next\" 15 characters: '$buffer2'\n";
$fh->close;

[download]

Output:

 1:17 >perl 1115_SoPW.pl

Enter a string: abcdefghijklmnopqrstuvwxyz

The first  10 characters: 'abcdefghij'
The "next" 15 characters: 'abcdefghijklmno'

 1:17 >

[download]

Update: Added print statements and renamed variables.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: peek at STDIN, to determine data type and then pass STDIN to a parser by Athanasius
in thread peek at STDIN, to determine data type and then pass STDIN to a parser by aral

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