Clearing the input stream

This is a discussion on Clearing the input stream within the C Programming forums, part of the General Programming Boards category; Someone told me to use this to clear input buffer Code: while((ch=getchar())!='\n' && ch!=EOF); ...and now this is giving me ...

  1. #1
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    Question Clearing the input stream

    Someone told me to use this to clear input buffer
    Code:
    while((ch=getchar())!='\n' && ch!=EOF);
    ...and now this is giving me a warning:
    Code:
    #include<stdio.h>
    int main()
    {
       char a,b,ch;
       printf("\nEnter a character:");
       a=getchar();
       while((ch=getchar())!='\n' && ch!=EOF);   
       printf("\nEnter another one:");
       b=getchar();
       while((ch=getchar())!='\n' && ch!=EOF);
       printf("You entered %c and %c\n",a,b);
       return 0;
    }
    13:3: warning: no newline at end of file

    The program works as expected, though.

  2. #2
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    The warning has nothing to do with the code you added, it simply says the compiler waits for a new line at the end of your source file (after the last }).

  3. #3
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    Why should the compiler wait for new line after the closing brace?

    ALL the programs I write end like this
    Code:
         /****************/
         /****************/
         return 0;
    }
    But the compiler never waits for a new line there.
    Last edited by abh!shek; 05-18-2008 at 06:32 AM.

  4. #4
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    Why should the compiler wait for new line after the closing brace?
    The C standard requires the source files to end by a new line character, that's all. In your case, it's after the }, I didn't said it always has to be after the last }.

  5. #5
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    What should I change/add in this source to get rid of the warning...? You know...I don't like getting compiler warnings.

  6. #6
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    Open the source file in your favorite editor, move the cursor to the very end and press enter, save and recompile.

  7. #7
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    Thanks that works

    The C standard requires the source files to end by a new line character, that's all.
    Can you give me a link to this reference?

  8. #8
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    Section 5.1.1.2 of the standard (http://www.open-std.org/jtc1/sc22/wg...docs/n1124.pdf)

  9. #9
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    Is that requirement in the C++ standard too?
    Someone told me some compilers require it, so I've always done it because I thought it was a compiler bug.

  10. #10
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    Is that requirement in the C++ standard too?
    Someone told me some compilers require it, so I've always done it because I thought it was a compiler bug.
    Yes, the C++ Standard requires that as well.
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  11. #11
    C++まいる!Cをこわせ! Elysia's Avatar
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    On a different line: why does it require it?
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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