Re: for loop in makefile

[Wayne Throop]

: address@hidden (Ed Wong)
: I need to have a simple loop in makefile to unzip and rename all the
: nc*.gz files in current directory.  The following is how I do it in
: shell script and I need to put it in makefile.  Anyone know how to do
: it?  Thanks in advance.
: 
: for file in `ls nc*.gz`
: do
:         base=`echo $file | awk -F. '{ print $1 }'`
:         $unzip $file
:         mv -f $base $base.txt
: done
: 
: ewong

One straightforward way is

    $(foreach f,$(basename $(wildcard nc*.gz)),gunzip $f.gz; mv -f $f $f.txt;)

but that may cause problems if there are enough files to overflow
the maximum shell argument list size... mildly unlikely, but possible.
So you could also do

    for file in `ls nc*.gz`;\
    do\
            base=`echo $$file | awk -F. '{ print $$1 }'`;\
            gunzip $$file;\
            mv -f $$base $$base.txt;\
    done

though it's considerably less efficient.
Slightly more efficient might be

    for file in nc*.gz;\
    do\
            base=`basename $$file .gz`;\
            gunzip $$file;\
            mv -f $$base $$base.txt;\
    done

( I'm assuming that "gunzip" was meant instead of "$unzip"...
  if not, make the necessary substitutions. )

Did your copy of GNU make not come with the documentation of
the builtin functions such as foreach, or the documentation of
the quoting rules for shell characters?


Wayne Throop   address@hidden   http://sheol.org/throopw