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:
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LEARN ABOUT CENTOS
fdformat
FDFORMAT(8) System Administration FDFORMAT(8)
NAME
fdformat - low-level format a floppy disk
SYNOPSIS
fdformat [options] device
DESCRIPTION
fdformat does a low-level format on a floppy disk. device is usually one of the following (for floppy devices the major = 2, and the minor
is shown for informational purposes only):
/dev/fd0d360 (minor = 4)
/dev/fd0h1200 (minor = 8)
/dev/fd0D360 (minor = 12)
/dev/fd0H360 (minor = 12)
/dev/fd0D720 (minor = 16)
/dev/fd0H720 (minor = 16)
/dev/fd0h360 (minor = 20)
/dev/fd0h720 (minor = 24)
/dev/fd0H1440 (minor = 28)
/dev/fd1d360 (minor = 5)
/dev/fd1h1200 (minor = 9)
/dev/fd1D360 (minor = 13)
/dev/fd1H360 (minor = 13)
/dev/fd1D720 (minor = 17)
/dev/fd1H720 (minor = 17)
/dev/fd1h360 (minor = 21)
/dev/fd1h720 (minor = 25)
/dev/fd1H1440 (minor = 29)
The generic floppy devices, /dev/fd0 and /dev/fd1, will fail to work with fdformat when a non-standard format is being used, or if the for-
mat has not been autodetected earlier. In this case, use setfdprm(8) to load the disk parameters.
OPTIONS
-n, --no-verify
Skip the verification that is normally performed after the formatting.
-V, --version
Output version information and exit.
-h, --help
Display help and exit.
SEE ALSO
fd(4), setfdprm(8), mkfs(8), emkfs(8)
AUTHOR
Werner Almesberger (almesber@nessie.cs.id.ethz.ch)
AVAILABILITY
The fdformat command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
util-linux July 2011 FDFORMAT(8)