I have a perl script example.pl that I run on linux box. I need to capture the output from the execution of the perl script and timestamp its name. I know the output redirection method but I am looking for a way to do it from the script example.pl itself (if possible)
3 Answers
It's easy to redirect the STDOUT to a file. Just do this at the beginning of the script:
open STDOUT, '>', "my_stdout_file.txt";
And this is a function that returns a file name with a timestamp:
sub generate_timestamp_filename {
my $tstamp = sprintf( "%04d%02d%02d%02d%02d%02d",
$now[5]+1900,
$now[4]+1,
$now[3],
$now[2],
$now[1],
$now[0] );
return "my_prefix_$tstamp.txt";
}
Comments
You can redirect output and error streams using Typeglobs or you can do the following.
#!/bin/perl
open(STDOUT, '>',time.".out") or die $!; #the time function gives you the timestamp
open(STDERR, '>',time.".err") or die $!;
print "output"; #goes to <timestamp>.out
warn "error"; #goes to <timestamp>.err
Comments
Here is the quickest way to do this:
open(STDOUT, ">myfile") or die $!;
print "Hello world"; #now goes to myfile
open(STDERR, ">hisfile") or die $!;
warn "Error here"; #and that's in hisfile
The other alternative is to use select:
open(my $FILE, ">stdout") or die $!;
my $old = select($FILE);
# Done capturing output
select $old;
1 Comment
ikegami
select will fail if someone uses STDOUT directly and won't be inherited by child processes, but it's easy to restore.