convoluted code Post: 302666549

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The Lounge War Stories convoluted code Post 302666549 by alister on Wednesday 4th of July 2012 05:23:49 PM

07-04-2012

Registered User

Quote:

Originally Posted by methyl

Footnote: For anybody following this thread, this is a discussion thread.
@jgt is expert and definitely did not ask this question.

I must confess that I was confused until that footnote clued me in to the fact that I wasn't in the shell scripting forum anymore (got here via the 'new posts' link). Smilie

Quote:

Originally Posted by methyl

Until looking at unix.com I had never seen the for var in <open-ended list> construct ever ... and still wonder which course/manual/book/rumour it comes from?

I don't know for certain, but my first impulse is to blame GNU Bash. I've seen that idiom recommended as the correct way to work around the fact that the final command in a bash pipeline runs in a subshell.

From the Advanced Bash-Scripting Guide's Bash Gotchas:

Code:

# Loop piping troubles.
#  This example by Anthony Richardson,
#+ with addendum by Wilbert Berendsen.


foundone=false
find $HOME -type f -atime +30 -size 100k |
while true
do
   read f
   echo "$f is over 100KB and has not been accessed in over 30 days"
   echo "Consider moving the file to archives."
   foundone=true
   # ------------------------------------
     echo "Subshell level = $BASH_SUBSHELL"
   # Subshell level = 1
   # Yes, we're inside a subshell.
   # ------------------------------------
done
   
#  foundone will always be false here since it is
#+ set to true inside a subshell
if [ $foundone = false ]
then
   echo "No files need archiving."
fi

# =====================Now, here is the correct way:=================

foundone=false
for f in $(find $HOME -type f -atime +30 -size 100k)  # No pipe here.
do
   echo "$f is over 100KB and has not been accessed in over 30 days"
   echo "Consider moving the file to archives."
   foundone=true
done
   
if [ $foundone = false ]
then
   echo "No files need archiving."
fi

Regards,
Alister

alister

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asadmin-delete-threadpool

asadmin-delete-threadpool(1AS)					   User Commands				    asadmin-delete-threadpool(1AS)

NAME

       asadmin-delete-threadpool, delete-threadpool - removes the named threadpool

SYNOPSIS

       delete-threadpool  --user  admin_user  [--password admin_password] [--host localhost] [--port 4848] [--secure|-s] [--passwordfile filename]
       [--terse=false] [--echo=false] [--interactive=true] threadpool_id

       Removes the threadpool with the named ID. This command is supported in remote mode only.

OPTIONS

       --user		       authorized domain application server administrative username.

       --password	       password to administer the domain application server.

       --host		       machine name where the domain application server is running.

       --port		       port number of the domain application server listening for administration requests.

       --secure 	       if true, uses SSL/TLS to communicate with the domain application server.

       --passwordfile	       file containing the domain application server password.

       --terse		       indicates that any output data must be very concise, typically avoiding human-friendly sentences and favoring well-
			       formatted data for consumption by a script. Default is false.

       --echo		       setting to true will echo the command line statement on the standard output. Default is false.

       --interactive	       if set to true (default), only the required password options are prompted.

OPERANDS

       threadpool_id	       an ID for the work queue; for example, thread-pool-1, thread-pool-2, etc.

       Example 1: Using delete-threadpool

       asadmin> delete-threadpool --user admin1 --password adminadmin1
       threadpool-1
       Command delete-threadpool executed successfully

EXIT STATUS

       0		       command executed successfully

       1		       error in executing the command

       asadmin-create-threadpool(1AS), asadmin-list-threadpools(1AS)

J2EE 1.4 SDK							    March 2004					    asadmin-delete-threadpool(1AS)