Please explain this code

[ChoCo]

    while(fgets(buffer,127,pInfile)!=NULL)
    {
        for(i = 0; buffer[i]; ++i)
        {
            buffer[i] = tolower(buffer[i]);
            printf("%c",buffer[i]);
            count[buffer[i] - 'a']++;
        }
    }

When I read text from a file,
i don't understand about the second argument of the for loop,
what does it mean for the for loop to run until buffer[i],
i don't understand the meaning of buffer[i] in the for loop argument
because usually it is sth like for(i=0; i<=5; i++)

Please explain me T___T;

[Salem]

It's the same as

buffer[i] != '\0'

In other words, all the chars up to the \0 at the end.

[ChoCo]

the end doesn't include space bar right?

[Salem]

Try it!

[ChoCo]

Thanks for helping !
This clear my confusion

[ChoCo]

May i ask a bit more,
what is the difference between these two
>while(fgets(buffer,127,pInfile)!=NULL)
>while ( fscanf( pInfile, "%s" , buffer ) != EOF )
or are they the same?

[Salem]

No they are not the same.

Assuming 127 is an honest statement of the size of the input buffer, fgets() will never overflow the buffer.
It will also read spaces.

The fscanf will not read spaces (as written), nor can it guarantee to never overflow the buffer.

[ChoCo]

so if i also want to count the frequency of the space then i should use the fgets one
because the fscanf doesn't read space, right?

[quzah]

It can, provided you use the correct format specifier. You could just do it the lazy way and use fgetc. You're going to be reading through each character at a time anyway.


Quzah.