http://qs1969.pair.com?node_id=537980


in reply to cmd.exe piping stress

Any ideas about how to proceed with debugging,

To see what is being received from the pipe, use a one-liner to receive and redirect it: 

perl units.pl COM1 < dmp4.tests > dmp4.results
perl units.pl COM1 < dmp4.tests | perl -pe1 > dmp4.piped

diff dmp4.results dmp4.piped

[download]

Then you can compare the two.

What are those COM1 references doing?

The comments mention warnings and errors. You are only piping/redirecting STDOUT not STDERR? Not that it should make any difference in what gets redirected or piped as STDERR would get displayed on the console in both cases--unless you are redirecting stuff internally to the program? To the serial port for example?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

Replies are listed 'Best First'.
Re^2: cmd.exe piping stress
by tomazos (Deacon) on Mar 20, 2006 at 17:10 UTC
    Th dmp4.results and the dmp4.piped are identical.

    When I then go and run:

    C:/> perl unit2summary.pl < dmp4.piped

    It works.

    When however I run it with "perl units.pl COM1 | perl unit2summary.pl" it doesn't work.

    The COM1 identifies the com port. It is part of a basic unit testing framework for a consumer electronics device.

    The code for unit2summary.pl follows: 

    #!perl

use strict;
use warnings;

my %results = ();
my $total;
my $command = '';
my $result = '';

while (<STDIN>) {
    chomp;
    next if /^\s*$/;

    if (/^COMMAND:\s+(.*)$/) {
        $command = $1;
    }

    if (/^RESULT:\s+(.*)$/) {
        $result = $1;
        print "$result: $command \n";
        $results{$result}++;
        $total++;
    }
    
}

print "\n";

print "TESTS: $total   ";
foreach (keys %results) {
    print "$_: " . $results{$_} . " (" . abs($results{$_} * 100 / $tot
+al) . "%)   ";
}
print "\n";

    [download]

    A sample of the dmp4.piped follows: 

    COMMAND: mc creation

    TIMEOUT: 3
    Creating various ContentData objects
    SUCCESS: Up-Casting HMediaAudioCD to HMediaCD
    SUCCESS: Up-Casting HMediaImageCD to HMediaCD
    SUCCESS: Up-Casting HMediaVideoCD to HMediaCD
    Working with const ContentData objects
    SUCCESS: Creation of new const-pointer HMediaAudioCD initialized w
+ith non-const handle
    SUCCESS: Up-casting constHMediaAudioCD to constHMediaCD
    SUCCESS: Const-Casting from constHMediaAudioCD to HMediaAudioCD
    SUCCESS: Down-casting from constHMediaCD to constHMediaAudioCD
    SUCCESS: Making Const from cpHACDconst to ccpCD not successful
    RETURN: 

RESULT: PASSED

COMMAND: mc attr

    TIMEOUT: 3
    Creating HMediaAudioCD and add Title Attribute
    SUCCESS: HMediaAudioCD created
    SUCCESS: Checking for attribute "title" 
    ERROR: Checking attribute value: This is my lif
    Changing value of Title attribute by re-adding with different valu
+e
    SUCCESS: Checking for attribute "title" (2nd time)
    SUCCESS: Checking if attribute value was updated
    SUCCESS: Checking No. of attributes: 1
    SUCCESS: Re-Checking No. of attributes: 1
    SUCCESS: Removing attribute
    ERROR: Checking if attribute was really removed
    Adding more attributes
    SUCCESS: Attribute 0 has value A
    SUCCESS: Attribute 1 has value B
    SUCCESS: Attribute 2 has value C
    SUCCESS: Attribute 3 has value D
    SUCCESS: Attribute 4 has value E
    SUCCESS: Removing attribute at index 1 in list
    SUCCESS: Trying to remove non-existing attribute at index 5
    ERROR: Removing all 4 Attributes: 4 elements left
    Checking setAttributeValue methods
    SUCCESS: Checking if setting value by name on non existing attribu
+te prohibited
    SUCCESS: Checking if setting value by index on non existing attrib
+ute prohibited
    SUCCESS: Setting value to new attribute
    SUCCESS: Re-setting value of existing attribute at index 0
    Testing const char* - interface
    Adding attribute using const char* interface 
    SUCCESS: Getting value of just added attribute
    SUCCESS: Checking if value of attribute is correct: somewhere over
+ the rainbow
    SUCCESS: Re-setting value of just added attribute using const char
+* interface
    SUCCESS: Getting value of just changed attribute
    SUCCESS: Checking if value of attribute is correct: somewhere over
+ the rainbow
    RETURN: 

RESULT: FAILED

    [download]

    Any help appreciated.

    -Andrew.

    Andrew Tomazos  |  andrew@tomazos.com  |  www.tomazos.com
[reply]
[d/l]
[select]
      C:/> perl unit2summary.pl < dmp4.piped

      Can I take it from the prompt shown in your command line that you are using some other shell than cmd.exe?

      If so, try your commands with cmd.exe. I can't see any difference in the behaviour here: 

      C:\test>perl -pe1 junk.dat | perl unit2summary.pl
PASSED: mc creation
FAILED: mc attr

TESTS: 2   PASSED: 1 (50%)  FAILED: 1 (50%)

C:\test>perl unit2summary.pl <junk.dat
PASSED: mc creation
FAILED: mc attr

TESTS: 2   PASSED: 1 (50%)  FAILED: 1 (50%)

      [download]
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]
        I use both cygwin and cmd.exe.

        In both situations I get the same results.

        I notice now that under cmd.exe it is finding the cygwin perl first in the path. Maybe it is the cygwin perl causing trouble.

        I'm reinstalling ActiveState and will put that first in my path, and see what that does.

        -Andrew.

        Andrew Tomazos  |  andrew@tomazos.com  |  www.tomazos.com
[reply]

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