#!/usr/bin/perl -w
#First example:
#Use select to redirect to FILE (which tees to STDOUT) or
#           to redirect to STDOUT

$my_perlhome = "/home/privera/perl";
$log_file = "$my_perlhome/logfile";
$log_file2 = "$my_perlhome/logfile2";
$log_file3 = "$my_perlhome/logfile3";
$log_file4 = "$my_perlhome/logfile4";
$log_file5 = "$my_perlhome/logfile5";

#Flush buffers
#$|=1;

print "First example: select\n";
open(FILE, "| tee $log_file") or die "Can't open: $!\n";
select (FILE);
print "Testing 1.2.3...\n";
close(FILE) or die "Can't close: $!\n";
select (STDOUT);
print "done\n";

#Second example:
#Uses local (notice braces)

print "\nSecond example: local\n";
print "Should go to stdout.\n";
{
        local *STDOUT;
        open (STDOUT,"| tee $log_file2") or die "Can't open: $!\n";
        print "Should go to second logfile and STDOUT\n";
}
print "Should go to stdout.\n";

#Third example:
#Uses SelectSaver
#Info from perldoc.com:
#"A SelectSaver object contains a reference to the file handle that
#was selected when it was created. If its new method gets an extra par
+ameter,
#then that parameter is selected; otherwise, the selected file handle
#remains unchanged.
#
#When a SelectSaver is destroyed, it re-selects the file handle
#that was selected when it was created."

print "\nThird example: SelectSaver\n";
use FileHandle;
use SelectSaver;
{

        my $newfh = new FileHandle("| tee $log_file3") or
                 die "Can't open: $!\n";
        my $saver = new SelectSaver($newfh);
        # <$newfh> is selected
        print "Should go to third logfile and STDOUT\n";
}
# previous handle (STDOUT) is selected
print "Should go to stdout.\n";

print "\nFourth example: select multiple\n";


open(FILE, "| tee $log_file4") or die "Can't open: $!\n";
select (FILE);
print "This is written to both STDOUT and the fourth logfile\n";
select (STDOUT);
print "This is written only to STDOUT\n";
select (FILE);
print "This next message is written to both STDOUT and the fourth logf
+ile\n";
close(FILE) or die "Can't close: $!\n";
select (STDOUT);
print "done\n";

print "\nFifth example: select multiple object oriented\n";
my $newfh = new FileHandle ("| tee $log_file5") or die "Can't open: $!
+\n";
select ($newfh);
print "This is written to both STDOUT and the fifth logfile\n";
select (STDOUT);
print "This is written only to STDOUT\n";
select ($newfh);
print "This next message is written to both STDOUT and the fifth logfi
+le\n";
close($newfh) or die "Can't close: $!\n";
select (STDOUT);
print "done\n";
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<privera> 121% select.pl
First example: select
Testing 1.2.3...
done

Second example: local
Should go to stdout.
Should go to second logfile and STDOUT
Should go to stdout.

Third example: SelectSaver
Should go to third logfile and STDOUT
Should go to stdout.

Fourth example: select multiple
This is written only to STDOUT
This is written to both STDOUT and the fourth logfile
This next message is written to both STDOUT and the fourth logfile
done

Fifth example: select multiple object oriented
This is written only to STDOUT
This is written to both STDOUT and the fifth logfile
This next message is written to both STDOUT and the fifth logfile
done
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