Problem with C code

[lkj]

I have a problem with the following  code:

Code: Select All | Copy To Clipboard

1 2 3

for(w = 0, w < levelheader->number_of_eggs, ++w){         //do something }

Where levelheader is a pointer to a struct:

Code: Select All | Copy To Clipboard

1 2 3 4 5

typedef struct LEVElHEADER{ //...     uint16_t number_of_eggs; //... }levelheader_t;

When I try to compile it, I get these errors :
test.c:7:18: warning: value computed is not used
test.c:7:54: error: expected ';'  before ')' token

I just can't find the problem

[calc84maniac]

In a for loop, you need to separate the statements with semicolons, not commas.

[lkj]

Thank you
Sometimes I make really silly mistakes...

[t0xic_kitt3n]

You're not alone, I kept on doing that for a while too

[Munchor]

By the way, you used "++w", shouldn't it be "w++"? I've seen both being used but I can't understand the different.

EDIT: Oh wait, I got it (http://www.gamedev.net/topic/337133-i-vs-i/)

[Ashbad]

By the way, you used "++w", shouldn't it be "w++"? I've seen both being used but I can't understand the different.

very different.  they both increment, but ++w applies before the value is taken into account, w++ applies after the whole line has been run through.

[Tribal]

By the way, you used "++w", shouldn't it be "w++"? I've seen both being used but I can't understand the different.

EDIT: Oh wait, I got it (http://www.gamedev.net/topic/337133-i-vs-i/)

Just as a side note, it is more efficient to do ++w.  So if you don't need the value of w before it's incremented, then use ++w instead.

[calcdude84se]

Just as a side note, it is more efficient to do ++w.  So if you don't need the value of w before it's incremented, then use ++w instead.

Except any good compiler will compile "w++" to the same as "++w" if the result isn't used. (I know the discussion ephan linked says that this might not be the case sometimes, but that's for C++) If precedent helps, I've always seen it written postfix for the loop increment.