I'm trying to diff files in different directories, but I don't want to
diff everything. The compiler produces subdirectories like debugger,
unshared, and profiled. I don't care what's in them, or if the .o
files are different. So far I've gotten this far:

export SRC=query_E
export TGT=query_D

find $SRC -name debugger -prune \
-o -name unshared -prune \
-o -name profiled -prune \
-o -name '*.c' -exec diff '{}' `echo {} | tr $SRC $TGT` \;

I don't know why tr isn't substituting $SRC for $TGT at all. It just
creates "diff query_E/... query_E/..."

What am I doing wrong?
I looked at someone else's solution which had an exec as follows:
-exec diff '{" $TGT
The problem is if find goes down more than 1 level, it will not match
$TGT anymore.

Thanks,
Craig

On Fri, 25 Apr 2008 15:24:19 -0700, Craig Hanna wrote:

> I'm trying to diff files in different directories, but I don't want to
> diff everything. The compiler produces subdirectories like debugger,
> unshared, and profiled. I don't care what's in them, or if the .o files
> are different. So far I've gotten this far:
>
> export SRC=query_E
> export TGT=query_D
>
> find $SRC -name debugger -prune \
> -o -name unshared -prune \
> -o -name profiled -prune \
> -o -name '*.c' -exec diff '{}' `echo {} | tr $SRC $TGT` \;
>
> I don't know why tr isn't substituting $SRC for $TGT at all. It just
> creates "diff query_E/... query_E/..."
>
> What am I doing wrong?
> I looked at someone else's solution which had an exec as follows: -exec
> diff '{" $TGT
> The problem is if find goes down more than 1 level, it will not match
> $TGT anymore.
>
> Thanks,
> Craig

There are several difficulties.

'tr' is not the program you want, it does a letter by letter
substitution, and you want a word by word change. Most people use "sed"
to do this.

A second problem is that the name conversion happens *before* the find is
run. As
echo {} | tr query_E query_D
is the same as
echo {} | tr E D
and there is no E in "{}", this gives
{}
so your find command is
find query_E -name debugger .... -exec diff '{}' '{}'

If I were writing this I would probably write it as this, assuming I knew
there were no funny characters in the filenames

find $SRC -name debugger -prune \
-o -name unshared -prune \
-o -name profiled -prune \
-o -name '*.c' -print | sed "s:$SRC/\(.*\):diff & $TGT/\1:"

and when I was happy that this was doing what I wanted, I would repeat
the command and put
| sh
onto the end of it to actually run it.