Thread: how do you use tolower()

  1. #1
    Registered User
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    Sep 2005
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    how do you use tolower()

    hello, I have a character array with a string in it and it has an uppercase letter, I'm trying to convert it to all lowercase letters, I heard that the function tolower can be used, i put the ctype.h header in but i can't get it to turn my capital letter to a lower case letter

    could anyone tell me what am I doing wrong, here is my code, it's pretty simple

    thank you

    Code:
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    
    main() {
           
    char word[] = "Hello"; 
    int n = 0;
    
    printf(" %s \n ", word);
    
    while ( n <= 3 ){
          
          tolower( word[n]);
          n++; }
          
          printf(" %s \n ", word);
    
    getchar();}

  2. #2
    Gawking at stupidity
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    tolower() can't store the modified character so you have to call it like:
    Code:
    word[n] = tolower( word[n] );
    If you understand what you're doing, you're not learning anything.

  3. #3
    Registered User TactX's Avatar
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    tolower() returns the converted letter. You have to write the returned value into your array word.

  4. #4
    Frequently Quite Prolix dwks's Avatar
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    For tolower() you should include <ctype.h>.
    dwk

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