Searching for newline on the end of line text

This is a discussion on Searching for newline on the end of line text within the C Programming forums, part of the General Programming Boards category; Hy everyone, I've searched high and low for the answer to this but am unable to find a decent answer. ...

  1. #1
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    Searching for newline on the end of line text

    Hy everyone,

    I've searched high and low for the answer to this but am unable to find a decent answer. The problem is simple, however, I am not a C programmer and its giving me migrane on how to do this.

    What I want to achive is simple:
    - I have a string, within, serveral lines of texts.
    - I need to find out, if the last character in the entire text is a newline.
    - if so, i need to add a string starting without a newline
    - of not, i need to add a string starting with a newline.

    I cannot seem to find a manner in how to verify the last character is newline or not. Remeber, the might be several newlines in the text present, I'm only intrested in the last newline.

    If anyone has any thoughts on this I would really appreciate it!

  2. #2
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    ftell( ) with SEEK_END will move your file pointer to the last char in the file.

    Now "walk" (move the file pointer), backward, until you reach the first char. If it's a newline, then just write your string.

    If it's not a newline, then write a newline, then write your string.

    An example of using ftell() in this way is here:

    Last line of a data file not wanted to be read in and the while statement

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    You can use the regexp functions regcomp() and regexec() to filter strings that end in a newline.

  4. #4
    Code Goddess Prelude's Avatar
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    >ftell( ) with SEEK_END will move your file pointer to <blah blah blah>
    >You can use the regexp functions regcomp() and regexec() to filter strings that end in a newline.
    What? You guys must be smoking something good to read so far between the lines, because this seems sufficient to me:
    Code:
    if (s[len - 1] == '\n') {
      /* Append a newline first */
    }
    else {
      /* Don't append a newline */
    }
    My best code is written with the delete key.

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    Quote Originally Posted by Prelude View Post
    What? You guys must be smoking something good to read so far between the lines, because this seems sufficient to me
    ROTFLOL
    Quote Originally Posted by Prelude View Post
    Code:
    if (s[len - 1] == '\n') {
      /* Append a newline first */
    }
    else {
      /* Don't append a newline */
    }
    Yup! that one's the best.

  6. #6
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    You gals must be half asleep to think that someone that new, who asks that basic a question, will know how to find the length of a file.

    ROFL

    Good to see you around again, Prelude. I always enjoy your posts, for real.
    Last edited by Adak; 03-02-2010 at 10:43 AM.

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    C++ Witch laserlight's Avatar
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    Quote Originally Posted by Adak
    You gals must be half asleep to think that someone that new, who asks that basic a question, will know how to find the length of a file.
    By using strlen(), of course
    C + C++ Compiler: MinGW port of GCC
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    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    Talking

    Quote Originally Posted by Prelude View Post
    >ftell( ) with SEEK_END will move your file pointer to <blah blah blah>
    >You can use the regexp functions regcomp() and regexec() to filter strings that end in a newline.
    What? You guys must be smoking something good to read so far between the lines, because this seems sufficient to me:
    Code:
    if (s[len - 1] == '\n') {
      /* Append a newline first */
    }
    else {
      /* Don't append a newline */
    }
    Thank you so much for this! I already tried something like this but had the structure and everything completely messed up! :P All other examples where like 30+ lines of code and i could not believe that it needed te be that difficult

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