atoi

This is a discussion on atoi within the C Programming forums, part of the General Programming Boards category; I am trying to let the user enter only a choice of 1,2or3 if the user enters a letter I ...

  1. #1
    Max
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    atoi

    I am trying to let the user enter only a choice of 1,2or3
    if the user enters a letter I want to give an error message.

    So far my program crashes if the user enters a char.

    I tryed to use atoi but it did not solve the problem....how can I solve it.....

    Code:
    printf("   choice: ");
    scanf("%d", &choice);
    
    if (isalpha(choice))
          choice=atoi(choice);
          fprintf(stderr,"incorrect choice, try again!\n");

  2. #2
    Skunkmeister Stoned_Coder's Avatar
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    dont use scanf. use fgets() and sscanf(). This subject has been covered many times. search the boards.
    basically make an array. fill it with user input with fgets(). use sscanf() to extract an int from the input. use if to make sure int is in range.
    Free the weed!! Class B to class C is not good enough!!
    And the FAQ is here :- http://faq.cprogramming.com/cgi-bin/smartfaq.cgi

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