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Full Discussion: Multiple jobs reading from same file
Top Forums Shell Programming and Scripting Multiple jobs reading from same file Post 302413134 by erichpowell on Wednesday 14th of April 2010 04:44:18 PM
Old 04-14-2010
Thanks, Franklin52, that's precisely what I had in mind, but what I was actually getting at was the safety of this technique.

I know that multiple processes writing to the same file is a recipe for trouble, understandably, but I was curious whether multiple jobs/processes reading from the same file is also dangerous.

For example, what happens if they both try to read the same block of memory at the same time?

My googling turned up some forum topics about this in C code, where it did seem to be an issue, but I was going to submit jobs to the background like in Franklin52's post. Can I rely on the OS to sort out any conflicts between the processes?
 

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GEARMAN_CLIENT_RUN_TASKS(3)					     Gearmand					       GEARMAN_CLIENT_RUN_TASKS(3)

NAME

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SYNOPSIS

       #include <libgearman/gearman.h>

       gearman_return_t gearman_client_run_tasks(gearman_client_st *client)

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DESCRIPTION

       gearman_client_run_tasks()  executes one or more tasks that have been added via gearman_client_add_task(), gearman_client_add_task_status()
       or gearman_client_add_task_background().

       gearman_client_run_tasks() can also be used with gearman_execute() if either non-blocking or background tasks were created with it.

RETURN VALUE

       gearman_return_t

       If GEARMAN_PAUSE is returned one of the tasks has "paused" in order to give the caller an opportunity to take some actions (like read data,
       handle an exception, etc...). See gearman_task_st for more information about the state of a task.

HOME

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       See also

	      gearmand(8) libgearman(3)

AUTHOR

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COPYRIGHT

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0.33								   May 04, 2012 				       GEARMAN_CLIENT_RUN_TASKS(3)
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