Help with dd array

[Singleton]

what is wrong with my main fn?



void f(char** p)

{

printf("%s", p[0]);

}



void main()

{

char a[50][50];

strcpy(a[0], "hello");

f(a);

}

[pemo]

Re: Help with dd array


"Singleton" <kuchbhi@homeca ll.co.uk> wrote in message
news:43874a5f$1 _4@mk-nntp-2.news.uk.tisca li.com...[color=blue]
> what is wrong with my main fn?
>
>
>
> void f(char** p)
>
> {
>
> printf("%s", p[0]);
>
> }
>
>
>
> void main()
>
> {
>
> char a[50][50];
>
> strcpy(a[0], "hello");
>
> f(a);
>
> }
>
>[/color]

Gosh, it's hard to know where to start ... but maybe you could say something
about what you expect this to be doing?

Something like this ...??

#include <stdlib.h>

void f(char * p)

{
printf("%c", p[0]);
}



int main(void)

{
char a[50][50];

a[0][0] = 'e';

f(&a[0][0]);
}

a is an array of 50 arrays of 50 characters. Is that what you thought it
was?

[Richard Heathfield]

Re: Help with dd array

Singleton said:
[color=blue]
> what is wrong with my main fn?
>
>
>
> void f(char** p)
>
> {
>
> printf("%s", p[0]);[/color]

Undefined behaviour - calling a variadic function without a function
prototype in scope. You forgot to #include <stdio.h>
[color=blue]
>
> }
>
>
>
> void main()[/color]

In C, main() returns int.
[color=blue]
>
> {
>
> char a[50][50];
>
> strcpy(a[0], "hello");[/color]

You'll want <string.h> as well, then.
[color=blue]
> f(a);[/color]

f takes char **, but you're not passing a char **. In a value context, the
name of an array decays into a pointer to its first element, so a has the
type char (*)[50], which is not the same as char **.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999

http://www.cpax.org.uk

email: rjh at above domain (but drop the www, obviously)