[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Wanted: bash enhancement... non-blocking 'wait'

From: Philip Prindeville
Subject: Re: Wanted: bash enhancement... non-blocking 'wait'
Date: Fri, 03 Sep 2010 13:12:06 -0700
User-agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv: Gecko/20100802 Thunderbird/3.1.2

 On 9/3/10 10:44 AM, Eric Blake wrote:
On 09/02/2010 04:44 PM, Philip Prindeville wrote:
I wanted to check in and see if there was a chance of this feature being
accepted upstream before I spent any time on it... so here goes.

The "wait [n]" command is handy, but would be even handier is:

wait [[-a] n]

instead, which asynchronously checks to see if process 'n' has completed.

What's wrong with using the existing 'kill -0 pid' to check if pid still 
exists, rather than inventing a new argument to 'wait'?

Well, in theory, if you waited long enough (to look for the process), and it 
had exited and a new process with that id was created, you'd detect the wrong 

At least with 'wait' you're guaranteed it's still in your process-group, right?

Besides, 'wait' is just a lot easier to read and understand... not everyone 
knows the system call semantics of kill().

reply via email to

[Prev in Thread] Current Thread [Next in Thread]