There may be more professional solutions, but if I'm only watching one variable, or just a few variables, and I don't wish to interrupt the process, what I have sometimes done is to print that variable to a file, in append mode. Then I check that file. With Linux, it's quite easy...just use tail -f filename.txt to see a running display of what is being added to the file...just like a log file.

Don't forget, of course, to output to the file in the appropriate encoding if you are not working with English.

Basically, I would just do something like this (untested): 

my $watchlog = '/tmp/watchlog.txt';

    printLog("Watch file: $watchlog\n"); #Whatever and wherever you wa
+nt to print


sub printLog { 
my $info = shift @_;

    open (LOG, '>>:encoding(utf8)', $watchlog) or die "Cannot open the
+ logfile. $!\n";
    print LOG $info;
    close LOG;

} #END SUB printLog

[download]

Blessings,

~Polyglot~

In reply to Re: how watch a variable by Polyglot
in thread how watch a variable by xiaoyafeng

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