1IPC::Run::Debug(3) User Contributed Perl Documentation IPC::Run::Debug(3)
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6 IPC::Run::Debug - debugging routines for IPC::Run
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9 ##
10 ## Environment variable usage
11 ##
12 ## To force debugging off and shave a bit of CPU and memory
13 ## by compile-time optimizing away all debugging code in IPC::Run
14 ## (debug => ...) options to IPC::Run will be ignored.
15 export IPCRUNDEBUG=none
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17 ## To force debugging on (levels are from 0..10)
18 export IPCRUNDEBUG=basic
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20 ## Leave unset or set to "" to compile in debugging support and
21 ## allow runtime control of it using the debug option.
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24 Controls IPC::Run debugging. Debugging levels are now set by using
25 words, but the numbers shown are still supported for backwards
26 compatibility:
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28 0 none disabled (special, see below)
29 1 basic what's running
30 2 data what's being sent/received
31 3 details what's going on in more detail
32 4 gory way too much detail for most uses
33 10 all use this when submitting bug reports
34 noopts optimizations forbidden due to inherited STDIN
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36 The "none" level is special when the environment variable IPCRUNDEBUG
37 is set to this the first time IPC::Run::Debug is loaded: it prevents
38 the debugging code from being compiled in to the remaining IPC::Run
39 modules, saving a bit of cpu.
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41 To do this in a script, here's a way that allows it to be overridden:
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43 BEGIN {
44 unless ( defined $ENV{IPCRUNDEBUG} ) {
45 eval 'local $ENV{IPCRUNDEBUG} = "none"; require IPC::Run::Debug"'
46 or die $@;
47 }
48 }
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50 This should force IPC::Run to not be debuggable unless somebody sets
51 the IPCRUNDEBUG flag; modify this formula to grep @ARGV if need be:
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53 BEGIN {
54 unless ( grep /^--debug/, @ARGV ) {
55 eval 'local $ENV{IPCRUNDEBUG} = "none"; require IPC::Run::Debug"'
56 or die $@;
57 }
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59 Both of those are untested.
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62 Barrie Slaymaker <barries@slaysys.com>, with numerous suggestions by
63 p5p.
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67perl v5.30.1 2020-01-30 IPC::Run::Debug(3)