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Full Discussion: How do you wait for command substitution processes to complete?
Top Forums UNIX for Dummies Questions & Answers How do you wait for command substitution processes to complete? Post 302398060 by methyl on Tuesday 23rd of February 2010 07:01:50 PM
Old 02-23-2010
Like "drl" I don't get exactly what you are tying to achieve. I can't see why there is the complexity of redirecting channels.

It seems that you want to issue multiple command sets concurrently and wait until they have all completed.

IMHO forget using exec. It will drive you nuts with multiple concurrent processes.

Best approach is to background the command (or lots of commands).
[CODE]nohup command_name &[/CODE

Then check for background jobs.
Code:
jobs

When there are no background jobs running, all the background jobs for your user have completed.

I'll leave you to script processing the output (or not!) from the shell command "jobs". See "man" for your shell to read about "jobs".
 

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LEARN ABOUT SUNOS

atq

atq(1)								   User Commands							    atq(1)

NAME

       atq - display the jobs queued to run at specified times

SYNOPSIS

       atq [-c] [-n] [username...]

DESCRIPTION

       The  atq  utility  displays the at jobs queued up for the current user. at(1) is a utility that allows users to execute commands at a later
       date. If invoked by a user with the solaris.jobs.admin authorization, atq will display all jobs in the queue.

       If no options are given, the jobs are displayed in chronological order of execution.

       When an authorized user invokes atq without specifying username, the entire queue is displayed; when a username is  specified,  only  those
       jobs belonging to the named user are displayed.

OPTIONS

       The following options are supported:

       -c	Displays the queued jobs in the order they were created (that is, the time that the at command was given).

       -n	Displays only the total number of jobs currently in the queue.

FILES

       /var/spool/cron/atjobs	       spool area for at jobs.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       at(1), atrm(1), auths(1), cron(1M), auth_attr(4), attributes(5)

SunOS 5.10							    13 Aug 1999 							    atq(1)
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