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Top Forums Programming Pointer for 2D array seems to be 3D in C Post 302999280 by Corona688 on Friday 16th of June 2017 11:13:22 AM
Old 06-16-2017
1) They probably differ in being constants or non-constants.

3) It's "3d" because you have an extra pointer in the way. Every level of pointers requires another dereferencing operation to access it. One level pointer requires one. Two level pointer requires two. Three level pointer requires three. 97 level pointer requires 97. That is the pattern.

The first dereferencing operation gets rid of is x itself; once you do so, you are essentially accessing y. The next level of pointers points to individual rows inside y. The last level gets you an individual cell in that row.

Code:
x; // pointer to Y
(*x); // Y, i.e. pointer to rows
(*x)[0]; // Pointer to row 0
(*x)[0][0] // Row 0 col 0.  No longer a pointer.

The diagram is x -> y -> row -> column.
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AUPARSE_INIT(3) 						  Linux Audit API						   AUPARSE_INIT(3)

NAME
auparse_init - initialize an instance of the audit parsing library SYNOPSIS
#include <auparse.h> auparse_state_t *auparse_init(ausource_t source, const void *b); DESCRIPTION
auparse_init initializes an instance of the audit parsing library. The function returns an opaque pointer to the parser's internal state. It is used in subsequent calls to the library so. The source variable determines where the library looks for data. Legal values can be: AUSOURCE_LOGS - use audit logs AUSOURCE_FILE - use a file AUSOURCE_FILE_ARRAY - use several files AUSOURCE_BUFFER - use a buffer AUSOURCE_BUFFER_ARRAY - use an array of buffers AUSOURCE_DESCRIPTOR - use a particular descriptor AUSOURCE_FILE_POINTER - use a stdio FILE pointer AUSOURCE_FEED - feed data to parser with auparse_feed() The pointer 'b' is used to set the file name, array of filenames, the buffer address, or an array of pointers to buffers, or the descriptor number based on what source is given. When the data source is an array of files or buffers, you would create an array of pointers with the last one being a NULL pointer. Buffers should be NUL terminated. RETURN VALUE
Returns a NULL pointer if an error occurs; otherwise, the return value is an aopaque pointer to the parser's internal state. SEE ALSO
auparse_reset(3), auparse_destroy(3). auparse_feed(3). AUTHOR
Steve Grubb Red Hat Feb 2007 AUPARSE_INIT(3)
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