Redirecting Standard Input C

Discussion in 'C' started by Chrystian_Vieyra, Jan 30, 2007.

  1. Chrystian_Vieyra

    Chrystian_Vieyra New Member

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    I am trying to redirect standard input to be a file, unfortunately I have not been succesful.

    My command in unix to execute my c applicacion is:

    a.out < file.something

    However, I receive a segmentation error.

    my c code to read that standard in is here:
    Code:
    void input()
    {
     char s[1];
     scanf("%c",s[1]);
     printf("Contents %c", s[1]);
    }
     
    Last edited by a moderator: Jan 30, 2007
  2. pradeep

    pradeep Team Leader

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  3. shabbir

    shabbir Administrator Staff Member

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    The segmentation error is you are defining the size of the array as 1 and you are doing the scanf in the position 1 but it should be at 0. Also you need to specify the address of the variable and not the variable.

    Try

    scanf("%c",&s[0]);

    Also you now know what you need to be doing with printf I guess.
     
  4. DaWei

    DaWei New Member

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    What's the point of a one-byte array? Why not just define a char? You also might as well redirect a line at a time since the standard libraries don't fetch a character at a time. They don't give you anything until the end of the line is encountered. You have to go implementation-specific for keystroke-level input.
     
    Last edited: Jan 30, 2007

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