Very Computer

How can I nest substituted commands? Here's what I need:

I have a directory e.g. /usr/velocity/spool/Queued/VBG-DWS-00001
What I need to extract is Queued.
Right now, I do something like this:

directory="/usr/velocity/spool/Queued/VBG-DWS-00001"
parent=`dirname $directory`
status=`basename $parent`

This works fine, but I would like to do something like this:

status=`basename `dirname $directory``

However, the above does not work, probably because the quoting is
screwed up. How do I do this right?

TIA

js

--
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-     Experience is knowing things, you should not do.      -
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Quote:>How can I nest substituted commands? Here's what I need:

>I have a directory e.g. /usr/velocity/spool/Queued/VBG-DWS-00001
>What I need to extract is Queued.
>Right now, I do something like this:

>directory="/usr/velocity/spool/Queued/VBG-DWS-00001"
>parent=`dirname $directory`
>status=`basename $parent`

>This works fine, but I would like to do something like this:

>status=`basename `dirname $directory``

>However, the above does not work, probably because the quoting is
>screwed up. How do I do this right?

--

"You can pay Uncle Sam with the overtime
 Is that all you get for your money?" --Billy Joel

find ${VBG_SPOOL} -type d -name $1-*-$2 \
                  -exec echo "`basename \`dirname {}\``" \;

but it always returns "."
Somehow it doesn't carry forward the curley braces because I tried this:

find ${VBG_SPOOL} -type d -name $1-*-$2 \
                  -exec echo "`basename \`dirname /foo/foo/bar\``" \;

which will return "foo". This proofs, that the -type and -name
evaluations were _true_ and -exec executes correctly.

Now what do I do????

TIA

js

--
-------------------------------------------------------------
-     Experience is knowing things, you should not do.      -
-------------------------------------------------------------

Quote:>I have a directory e.g. /usr/velocity/spool/Queued/VBG-DWS-00001
>What I need to extract is Queued.
>Right now, I do something like this:
>directory="/usr/velocity/spool/Queued/VBG-DWS-00001"
>parent=`dirname $directory`
>status=`basename $parent`
>This works fine, but I would like to do something like this:
>status=`basename `dirname $directory``

status=`basename \`dirname $directory\``

A cleaner way to do the same might be

status=`echo $directory | awk -F/ '{print $5}'`

Regards,
Gora

Quote:>However, now I'm stuck with another problem: I really would like to use
>this in the find -exec evaluation:
>find ${VBG_SPOOL} -type d -name $1-*-$2 \
>                  -exec echo "`basename \`dirname {}\``" \;
>but it always returns "."
>Somehow it doesn't carry forward the curley braces [...]

The second thing to note is that parameter and command
substitution is not done by find nor by echo. It is done by
the shell which You use to invocate find. The command word
given to echo in Your example below is constructed by the
shell which invocates find with the following parameters:

#0: find
#1: ???         (contents of variable VBG_SPOOL)
#2: -type
#3: d
#4: -name
#5: ???-*-???   (depends on contents of variables 1 and 2)
#6: -exec
#7: echo
#8: foo
#9: ;

Quote:>find ${VBG_SPOOL} -type d -name $1-*-$2 \

Quote:>                  -exec echo "`basename \`dirname /foo/foo/bar\``" \;

find ... -e sh -c 'basename `dirname "$1"`' sh '{}' ';'

Suppose, find has found the file
/dir/subdir/some-file-name; then it calls the bourne shell
with 4 parameter words (listed literally how the shell sees
them):

#1: -c
#2: basename `dirname "$1"`
#3: sh
#4: /dir/subdir/some-file-name

The shell then discards the 3rd word and sets its OWN
positional parameters $1, $2, ... to the remaining words
(no. 4 up): $1 becomes /dir/subdir/some-file-name

The program basename writes to standard output, so there is
no need to capture basename's output with `...` and give it
to echo: Instead of
   echo `basename ...`
write
   basename ...

If You write sh -c 'exec basename ...' rather than
sh -c 'basename ...', the shell does not fork a subprocess
to execute basename but replaces itself with basename thus
reducing the risk of running short of processes.

Regards, Friedhelm.

Quote:>How can I nest substituted commands? Here's what I need:

>I have a directory e.g. /usr/velocity/spool/Queued/VBG-DWS-00001
>What I need to extract is Queued.
>Right now, I do something like this:

>directory="/usr/velocity/spool/Queued/VBG-DWS-00001"
>parent=`dirname $directory`
>status=`basename $parent`

>This works fine, but I would like to do something like this:

>status=`basename `dirname $directory``

>However, the above does not work, probably because the quoting is
>screwed up. How do I do this right?

        status=$(basename $(dirname $directory))

If your shell does not support that syntax, use backslashes to escape
the inner backquotes:

        status=`basename \`dirname $directory\``

--
``The lyf so short, the craft so long to lerne.'' - Chaucer

    find ... -print | awk -F/ '{ print $(NF-1) }'

--

UniSoft Limited, London, England.

Yahoo!!

Every once in while someone realizes that explaining the root of problem
is more effective than providing the quick fix.
I pinned this email too my wall. Learned a lot!

Thanks again and have a Merry Christmas.

juergen

--
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-     Experience is knowing things, you should not do.      -
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