$commhist{$command}->$now which is distinctly not what it actually is.

It is used in the clean up function. Incidentally, this fixes a really
annoying issue where the check timeout functionality broken. The cause of the
check timeout functionality breaking was a scoping issue - the reader file
handle falls out of scope when the alarm fires and dies, and it waits until
the process finishes before passing control back to resmon. Storing the file
handle prevents it from being cleaned up until after we kill the process in
the clean_up function later on.

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@416 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

The original intent was to fix bad behavior when a command doesn't exist. Upon
looking further into the implementation of the run_command function, I
realized that using open achieved the same effect (backticks but we get a
process id out of it) without a lot of code that didn't quite work when the
exec failed.

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@414 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

When it does this, commands are not executed via the shell, but are executed
directly. (See the documentation for 'exec' for an explanation of this).
Existing modules that pass a string are unaffected.

The rationale for this change is for the Pgrep (and similar) modules, where it
was picking up the 'sh -c pgrep' process and including it in the process
count. Executing pgrep directly prevents this.

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@309 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@294 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@287 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@279 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/trunk@261 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/trunk@241 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

When a check times out using alarm, any processes launched using cache_command
or backticks would still be running, and leave a pipe open, even after the
process exits. This change keeps track of any child processes, and will kill
them off and clean up the pipe if a check timeout occurs. Modules that use
cache_command do not need any modification, but modules that use backticks
should change to using Resmon::ExtComm::run_cmd, which is a drop in
replacement. (use run_cmd("command") instead of `command`).

git-svn-id: https://labs.omniti.com/resmon/trunk@240 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

git-svn-id: https://labs.omniti.com/resmon/trunk@20 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55