Passing multi-dimensional array to function in c?

Question

I have an array of string declared like so:

char parts[PART_COUNT][PART_MAX];

Then i made a function which takes a string and a array of strings and splits it into those parts, which is declared like this:

WORD PartString(const char *str, char **parts, char sep);

I can seem to read at parts[i][j], but if i try to assign like this:

parts[i][j] = str[x];

I get this error:

Unhandled exception at 0x012614d8 in remote.exe: 0xC0000005: Access violation writing location 0xcccccccc.

Can anyone tell me a way to do this in C? thanks.

`char parts[M][N]` is not the same as `char **parts`; if you've performed a cast in order to get the compiler to stop complaining, then that will be the cause of your problem. — Oliver Charlesworth, Jul 03 '11 at 18:38
possible duplicate of [Converting multidimensional arrays to pointers in c++](http://stackoverflow.com/questions/1584100/converting-multidimensional-arrays-to-pointers-in-c) — Oliver Charlesworth, Jul 03 '11 at 18:40
compiler isn't complaining, i passed simply as PartString(buffer, parts, '.'); — Kaije, Jul 03 '11 at 18:40
That should definitely cause a compiler warning or error message. — Oliver Charlesworth, Jul 03 '11 at 18:41
the solution to the duplicate you linked, is to use a template. and its in c++ — Kaije, Jul 03 '11 at 18:42
You urgently need to deal with the fact that your compiler is broken. — David Heffernan, Jul 03 '11 at 18:44
@David: or perhaps its warnings are just not turned up enough. Kaije, if you're using gcc to compile, add the options `-Wall -Werror`. — John Zwinck, Jul 03 '11 at 18:47
i'm in visual studio, just enabled warnings, and it does warn me about it 'char **' differs in levels of indirection from 'char [4][1024]' — Kaije, Jul 03 '11 at 18:49
@John You are right. C is more permissive. Treat warnings as errors is the way forward and you could argue doing so is fixing the compiler!! ;-) — David Heffernan, Jul 03 '11 at 18:51

score 1 · Accepted Answer · edited Jul 03 '11 at 18:56

#define PART_MAX      1024
#define PART_COUNT    4

Ok, managed to fix it, i had my compiler warnings off and when i turned them back on i got this:

'char **' differs in levels of indirection from 'char [4][1024]'

Heres the new declaration which lets me modify the strings in the array:

WORD PartString(const char *str, char (*parts)[PART_MAX], char sep)

THen i just pass as:

PartString(buffer, parts, '.');

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