Under Windows the result of: 

C:/> perl a.pl | perl b.pl

[download]

differs from 

C:/> perl a.pl > f
C:/> perl b.pl < f

[download]

The specific example is: 

D:\tmp3>perl units.pl COM1 < dmp4.tests | perl unit2summary.pl
: test selftest randunit
: test selftest ok    # includes all except errors and warnings
: test selftest       # includes all except errors
: test selftest all  # includes also errors and warnings
: mc creation
: mc attr
: mc resdata
: mc container
: mc clone

 1 (11.1111111111111%)   TENTATIVE

D:\tmp3>perl units.pl COM1 < dmp4.tests > dmp4.results

D:\tmp3>perl unit2summary.pl < dmp4.results
PASSED: test selftest randunit
PASSED: test selftest ok    # includes all except errors and warnings
TENTATIVE: test selftest       # includes all except errors
FAILED: test selftest all  # includes also errors and warnings
PASSED: mc creation
FAILED: mc attr
PASSED: mc resdata
PASSED: mc container
PASSED: mc clone

TESTS: 9   PASSED 6 (66%)   TENTATIVE 1 (11%)   FAILED 2 (22%)

D:\tmp3>

[download]

I can't explain it. The only difference I see is when I print out multiple local my variables in one print, the characters get corrupted somehow.

Has anyone seen something like this before?

Any ideas about how to proceed with debugging, I'm stumped.

Could it have something to do with cygwin perl? I have both cygwin perl and activestate installed on my machine.

-Andrew.

Andrew Tomazos  |  andrew@tomazos.com  |  www.tomazos.com

In reply to cmd.exe piping stress by tomazos

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