NAME

dip - Dynamic instrumentation like DTrace, using aspects

SYNOPSIS

# run a dip script from a file; pass perl switches after the '--'
$ dip -s toolkit/count_new.dip -- -S myapp.pl

# run an inline dip script
$ dip -e 'before { count("constructor", ARGS(1), ustack(5)); $c{total}++ }
    call "URI::new"' test.pl

# a more complex dip script
$ cat quant-requests.dip
# quantize request handling time, separated by request URI
before { $ts_start = [gettimeofday] }
    call 'Dancer::Handler::handle_request';
after { quantize ARGS(1)->request_uri => 10**6*tv_interval($ts_start) }
    call qr/Dancer::Handler::handle_request/;
$ dip -s request-quant.dip test.pl
...
/
       value  ------------------ Distribution ------------------ count
        1024 |                                                   0
        2048 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@    95
        4096 |@@                                                 4
        8192 |                                                   0
       16384 |@                                                  1
       32768 |                                                   0

/login
       value  ------------------ Distribution ------------------ count
         512 |                                                   0
        1024 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                70
        2048 |@@@@@@@@@@@@@@@                                    30
        4096 |                                                   0

# The next example relies on Aspect::Library::Profiler, so
# if something goes wrong, you need to look in the Aspect modules.
$ dip -e 'aspect Profiler => call qr/^Person::set_/' myapp.pl

NOTE

This is the documentation for the dip program. If you are looking for the documentation on the dip module, use perldoc dip.pm or man 3 dip.

DESCRIPTION

dip is a dynamic instrumentation framework for troubleshooting Perl programs in real time. dip can provide fine-grained information, such as a log of the arguments with which a specific function is being called.

Please see the documentation of the dip module for more information (perldoc dip.pm).

COMMANDS

-s, --script

Takes a path to the dip script that should be run. This and the --exec option can be given several times and interleaved; they will be executed in the given order. For example:

dip -s foo.dip -e 'before { say "Hi" } call "Baz::new"' -s baz.dip

will result in the following code:

run q!foo.dip!;
before { say "Hi" } call "Baz::new";
run q!baz.dip!;
-e, --exec

Expects a dip script to be passed inline, much like perl -e expects an inline program.

-d, --delay

Tells dip not to activate the instrumentation at the beginning of the program. Instead the program to be instrumented should activate it manually using:

$dip::dip && $dip::dip->();

This is useful if your program loads other code that should be instrumented at runtime. For example, to test a web application that uses Plack you might use:

use Plack::Util;
use Plack::Test;
use HTTP::Request;

test_psgi
    app => Plack::Util::load_psgi('mywebapp.pl'),
    client => sub {
        my $cb = shift;
        # now we're sure that mywebapp.pl has been loaded
        $dip::dip && $dip::dip->();
        # ... now make requests and test the responses ...
    };
-v, --verbose

This option can be given several times; it will be available to the instrumentation code as well. In verbose mode, dip prints the command that is actually used to instrument the target program.

-f, --define

With this option you can pass values to the dip scripts. This option can be given several times and each time expects an argument of the form key=value. In the instrumentation code, these options are available in %opt.

SEE ALSO

dip

AUTHOR

The following person is the author of all the files provided in this distribution unless explicitly noted otherwise.

Marcel Gruenauer <marcel@cpan.org>, http://perlservices.at

COPYRIGHT AND LICENSE

The following copyright notice applies to all the files provided in this distribution, including binary files, unless explicitly noted otherwise.

This software is copyright (c) 2011 by Marcel Gruenauer.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.