Pointer question: *ptr with gets()

Hi everyone:

I wonder why when i use gets() function in statement generates an error, but when used with a pointer: *ptr it works fine:

" if (gets(input) != NULL) " -----generate an error
" if (*(ptr=gets(input) !=NULL)" -----works fine

what exactly does the pointer do here exactly??

Hopfully all those experienced programmers can answer this question....

ty.

Can you give us some more code to work with? Like a little example that does what you're talking about?

Code:

/* Little example */
#include <stdio.h>

int main(void)
{
    char line[10];

    if (gets(line) != NULL)
        puts("Woohoo! It works!");

    return 0;
}

yah..just exactly like wat u have......

Then I have no idea, it works fine for me. Try using fgets instead of gets and see how that works.

Code:

/* Little example */
#include <stdio.h>

int main(void)
{
    char line[10];

    if (fgets(line, sizeof (line), stdin) != NULL)
        puts("Woohoo! It works!");

    return 0;
}

Or if that doesn't work, you can use scanf.

Code:

/* Little example */
#include <stdio.h>

int main(void)
{
    char line[10];

    if (scanf("%9s", line) == 1)
    {
        int c;

        if ((c = getc(stdin)) != '\n' && c != EOF)
            ungetc(c, stdin);

        puts("Woohoo! It works!");
    }

    return 0;
}

Or write your own if you really need to.

@muk_luk
>>when i use gets() function in statement generates an error
Knowing what the error actually is might gives a bit more of a clue. Post some code too if you want help.

If you want more information, try here too.

[edit]
>>" if (*(ptr=gets(input) !=NULL)" -----works fine
This won't work fine, it doesn't have enough brackets, and therefore won't compile.

Originally posted by Hammer

>>" if (*(ptr=gets(input) !=NULL)" -----works fine
This won't work fine, it doesn't have enough brackets, and therefore won't compile.

Well actually, it depends. He does have it in quotes, so it's just a string literal.

Quzah.

Originally posted by muk_luk
Hi everyone:

I wonder why when i use gets() function in statement generates an error, but when used with a pointer: *ptr it works fine:


ty.

as i see , no one gave u the answer till now,
the answer for ur question is the following,

u should first determine the function prototype for gets
here it is

char *gets(char *s)
that means that this function reads character string and puts this string in a string s {pointer]

that is why u should use it with pointer

Originally posted by system_eyes
as i see , no one gave u the answer till now,

No, that has nothing to do with why he didn't get an answer. He didn't get an answer he liked because he failed to provide enough code. What is 'input' in his code? Can you be sure? No, you can't. He never says what 'input' is.

Furthermore, the provided code that he says works wouldn't even compile, because he doesn't have enough ) marks.

And finally, he never says what error he gets. Simply stated, he says "generates an error". Well that's all fine and dandy, but it does absolutely nothing for us when we're trying to tell him what he's doing wrong.

In short, if he had avoided gets all together, he wouldn't be having that problem.

Quzah.

thank you for all ur help.....


p.s: Quzah= stubbornnnnnn!

>> *(ptr=gets(input)

Oh God! Are you sure about the language you are writing in?