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Full Discussion: /dev/null file issue
Operating Systems AIX /dev/null file issue Post 302772427 by alister on Monday 25th of February 2013 01:14:49 PM
Old 02-25-2013
Disclaimer: I have never used AIX. Everything I say below is based on the OP's statement that /dev/null is a regular file.

Quote:
Originally Posted by Corona688
Take my advice with a grain of salt since I'm not an AIX expert, but: Having a /dev/null that is not a character device could be a big problem, yes! Things might create huge files in it, expecting them to go into the bit bucket, but actually ending up on disk instead... Some memory mapping things might not work right... etc.
Although a less common scenario, there are times when using /dev/null for reading is useful. One example that comes to mind is with grep, to force its output to include filenames, you may explicitly list /dev/null in a find -exec predicate or an xargs invocation, to ensure that grep is never called with a single file argument. If /dev/null does not yield nothing but EOF ... woe.

Regards,
Alister
Last edited by alister; 02-25-2013 at 02:26 PM..
This User Gave Thanks to alister For This Post:
jayadeava
 

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LEARN ABOUT DEBIAN

mkdevmaps

mkdevmaps(1M)						  System Administration Commands					     mkdevmaps(1M)

NAME

       mkdevmaps - make device_maps entries

SYNOPSIS

       /usr/sbin/mkdevmaps

DESCRIPTION

       The  mkdevmaps  command	writes	to standard out a set of device_maps(4) entries describing the system's frame buffer, audio, and removable
       media devices.

       The mkdevmaps command is used by the init.d(4) scripts to create or update the /etc/security/device_maps file.

       Entries are generated based on the device special files found in /dev. For the different  categories  of  devices,  the	mkdevmaps  command
       checks for the following files under /dev:

       audio	       /dev/audio, /dev/audioctl, /dev/sound/...
       tape	       /dev/rst*, /dev/nrst*, /dev/rmt/...
       floppy	       /dev/diskette, /dev/fd*, /dev/rdiskette, /dev/rfd*
       removable disk  /dev/dsk/c0t?d0s?, /dev/rdsk/c0t?d0s?
       frame buffer    /dev/fb

ATTRIBUTES

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

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Obsolete			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       allocate(1), bsmconv(1M), attributes(5)

NOTES

       mkdevmaps might not be supported in a future release of the Solaris operating system.

SunOS 5.10							    8 Oct 2003							     mkdevmaps(1M)
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