char[] vs LPCSTR strange behavior

Question

Could you please explain why, in order to convert a char array like this:

char strarr[5] = {65,83,67,73,73}; //ASCII

Into LPCSTR to be accepted by GetModuleHandleA() and GetProcAddress(), I have to first append 0 to the end ?

i.e. I have:

char strarr[6] = {65,83,67,73,73,0};

And only then convert as (LPCSTR)&strarr.

For some reason I don't get the first one works only sometimes (i.e. if I do not add 0 at the end), while if I do add zero at the end - this work all the time. Why do I have to add zero?

Oh and a side question - why in C++ do I have to explicitly state the size of array in [], when I am initializing it with elements right away? (If I don't state the size, then it does not work)

Thanks.

I made your question a little bit more readable. Please, do it yourself next time to give your questions better chances of being answered. — ereOn, May 26 '12 at 08:09

score 3 · Accepted Answer · answered May 26 '12 at 08:11

3

Those functions expect NULL terminated strings.

Since you only give them a pointer to a char array, they can't possibily know its size, hence the need for a particular value (the terminating NULL character) to indicate the end of the string.

answered May 26 '12 at 08:11

ereOn

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Oh I see. Thanks for a quick answer. Do I also have to append 0 to char arrays when expected value is const char * and not LPCSTR? – Fit Dev May 26 '12 at 08:13
1

Its ASCII `NUL` character, and not `NULL`. – UltraInstinct May 26 '12 at 08:28
@George Yes, almost all strings in C are null-terminated character arrays. – Cody Gray - on strike May 26 '12 at 08:40
@George: `LPCSTR` is actually a `define` for `const char*` so yes :) – ereOn May 26 '12 at 09:00

char[] vs LPCSTR strange behavior

1 Answers1