RE: GNU Make problem with $(shell ... )

[Paul D. Smith]

%% address@hidden writes:

  tm> Every time I build an executable I append some information about the
  tm> build to a log file. This is done with a perl script called in one of
  tm> the makefile rules. The script tags this information with a unique
  tm> serial number, and sends this number to stdout.

  tm> What I need to do is create a copy of the exe, and rename it with this
  tm> unique number so I can keep track of which exes are available.

  tm> So what I was hoping to do was basically something like this:

  tm> a.exe : a.obj b.obj
  tm>   lnk a.obj b.obj $@
  tm>   perl build_log.pl $(build_options) > new.number
  tm>   cp a.exe $(shell cat new.number).exe

Why don't you just use _shell_ expansion?

> a.exe : a.obj b.obj
>       lnk a.obj b.obj $@
>       perl build_log.pl $(build_options) > new.number
>       cp a.exe `cat new.number`.exe

Or, heck, just do it like this:

> a.exe : a.obj b.obj
>       lnk a.obj b.obj $@
>       cp a.exe `perl build_log.pl $(build_options)`.exe

and save yourself a bunch of shell/etc. invocations.

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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 "Please remain calm...I may be mad, but I am a professional." --Mad Scientist