Checking value of one character in array

This is a discussion on Checking value of one character in array within the C Programming forums, part of the General Programming Boards category; Very simple problem here, I just don't understand why this isn't working. Code: if(current_dir[(strlen(current_dir) - 3)] == '.') given that ...

  1. #1
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    Checking value of one character in array

    Very simple problem here, I just don't understand why this isn't working.

    Code:
    if(current_dir[(strlen(current_dir) - 3)] == '.')
    given that current_dir is:
    /cygdrive/c/dirent_tests/fssw.exe

    the if statement should be true, right? No matter what I do it's always false, what's up?

    -System_159

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    and the Hat of Guessing tabstop's Avatar
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    There are 33 characters + a '/0', so strlen gives 33. The '.' character is current_dir[29], so it looks like you should subtract 4.

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    Captain Crash brewbuck's Avatar
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    Quote Originally Posted by tabstop View Post
    There are 33 characters + a '/0', so strlen gives 33. The '.' character is current_dir[29], so it looks like you should subtract 4.
    Also, this code seems to assume that all extensions are three letters long. Better to use strrchr() to locate the last '.' in the string. Everything to its right is the extension.

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    Quote Originally Posted by brewbuck View Post
    Also, this code seems to assume that all extensions are three letters long. Better to use strrchr() to locate the last '.' in the string. Everything to its right is the extension.
    The only extensions I'll be using are 3 characters long, which is why I've done it this way.

    tabstop, thanks for pointing that out(again). Hopefully from now on I'll remember the damn '/0' !

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    Captain Crash brewbuck's Avatar
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    Quote Originally Posted by System_159 View Post
    The only extensions I'll be using are 3 characters long, which is why I've done it this way.
    "The only bullets I'll be firing are blanks, so that's why I'm pointing the gun at my head."


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    C++まいる!Cをこわせ! Elysia's Avatar
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    Quote Originally Posted by tabstop View Post
    There are 33 characters + a '/0', so strlen gives 33. The '.' character is current_dir[29], so it looks like you should subtract 4.
    I believe that's '\0'.
    '/' is not an escape character to my knowledge.
    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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    Quote Originally Posted by Elysia View Post
    I believe that's '\0'.
    '/' is not an escape character to my knowledge.
    You're right,absolutely

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    Chinese pâté foxman's Avatar
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    By the way, this is not due to the fact the last character of a string is '\0' but because the first element of an array is at index 0.

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