replacing scanf with fgets

This is a discussion on replacing scanf with fgets within the C Programming forums, part of the General Programming Boards category; float value; Code: scanf("%f", &libry[count++].value); I know I can replace the scanf() with atoi and fgets but how big should ...

  1. #1
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    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?
    ~flood

  2. #2
    Registered User caroundw5h's Avatar
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    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

  3. #3
    Gawking at stupidity
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    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.
    Last edited by itsme86; 08-18-2004 at 07:22 PM.
    If you understand what you're doing, you're not learning anything.

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    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
    ~flood

  5. #5
    Gawking at stupidity
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    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.
    Last edited by itsme86; 08-18-2004 at 07:30 PM.
    If you understand what you're doing, you're not learning anything.

  6. #6
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    again thanks man.

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

  7. #7
    ATH0 quzah's Avatar
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    You could have always just read the FAQ entry.

    Quzah.
    Hope is the first step on the road to disappointment.

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