Thread: replacing scanf with fgets

float value;

Code:

scanf("%f", &libry[count++].value);

I know I can replace the scanf() with atoi and fgets but how big should the buffer be? I'm not too sure how fgets works so I have a few questions concerning fgets.

Code:

fgets(str, 40, stdin)

The above line of code would read in 40 - 1 characters correct? If so what is stored in str[39]?null terminator?

If all 39 characters are read than does the newline stay in the input buffer?

I know I can replace the scanf() with atoi and fgets

don't know about that... might wanna look into how atoi works again. it doesn't replace scanf.

response to how fgets works

Big Edit: I originally wrote this lengthy reply answering all of the questions, but I'd instead like to encourage the original poster to create a simple test program (10 lines is all it takes) that answers the questions for him.

thanks itsme86!!

I have one problem though, how can I make sure that anything after 39 characters doesn't go to the input buffer? For example, the gets function would discard the newline character.


edit: too late I already read your post LOL

A simple way to clear everything after the fgets() up through the newline character would be to do something like:

Code:

while(getchar() != '\n')
  ;

...after the fgets(). Of course, you'll want to make sure the newline didn't get sucked out of the buffer during the fgets() call first

EDIT: Well, use the test program advice for future reference then.

again thanks man.

I use the strchr() function to find newline characters and replace them with the null terminator.

You could have always just read the FAQ entry.

Quzah.