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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..
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index(3C)						   Standard C Library Functions 						 index(3C)

NAME
index, rindex - string operations SYNOPSIS
#include <strings.h> char *index(const char *s, int c); char *rindex(const char *s, int c); DESCRIPTION
The index() and rindex() functions operate on null-terminated strings. The index() function returns a pointer to the first occurrence of character c in string s. The rindex() function returns a pointer to the last occurrence of character c in string s. Both index() and rindex() return a null pointer if c does not occur in the string. The null character terminating a string is considered to be part of the string. USAGE
On most modern computer systems, you can not use a null pointer to indicate a null string. A null pointer is an error and results in an abort of the program. If you wish to indicate a null string, you must use a pointer that points to an explicit null string. On some machines and with some implementations of the C programming language, a null pointer, if dereferenced, would yield a null string. Though often used, this practice is not always portable. Programmers using a null pointer to represent an empty string should be aware of this portability issue. Even on machines where dereferencing a null pointer does not cause an abort of the program, it does not necessarily yield a null string. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
bstring(3C), malloc(3C), string(3C), attributes(5), standards(5) SunOS 5.10 24 Jul 2002 index(3C)
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