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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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kva_match(3SECDB)				  Security Attributes Database Library Functions				 kva_match(3SECDB)

NAME
kva_match - look up a key in a key-value array SYNOPSIS
cc [ flag... ] file...- lsecdb [ library... ] #include <secdb.h> char *kva_match(kva_t *kva, char *key); DESCRIPTION
The kva_match() function searches a kva_t structure, which is part of the authattr_t, execattr_t, profattr_t, or userattr_t structures. The function takes two arguments: a pointer to a key value array, and a key. If the key is in the array, the function returns a pointer to the first corresponding value that matches that key. Otherwise, the function returns NULL. RETURN VALUES
Upon successful completion, the function returns a pointer to the value sought. Otherwise, it returns NULL. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ |ATTRIBUTE TYPE |ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
getauthattr(3SECDB), getexecattr(3SECDB), getprofattr(3SECDB), getuserattr(3SECDB) NOTES
The kva_match() function returns a pointer to data that already exists in the key-value array. It does not allocate its own memory for this pointer but obtains it from the key-value array that is passed as its first argument. SunOS 5.11 12 Aug 1999 kva_match(3SECDB)
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