passing variable to UNIX command

This is a discussion on passing variable to UNIX command within the C Programming forums, part of the General Programming Boards category; Hi, I trying to pass a variable to some unix commands and I'm not sure how to do it: Example: ...

  1. #1
    Registered User
    Join Date
    Oct 2009
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    2

    passing variable to UNIX command

    Hi,
    I trying to pass a variable to some unix commands and I'm not sure how to do it:
    Example:

    char *string_ptr;
    char unix_cmd[200];

    char unix_string1[]="echo ";
    char unix_string1[]=" | cc=`grep -a \"ControlID\"| cut -c 375-378`";


    main( ArsCSXitPrepExit *prep, char *argv[] )
    {
    int rc;
    string_ptr=strcat(unix_cmd,unix_string1);
    string_ptr=strcat(unix_cmd,argv[1]); <<<<< variable to pass
    string_ptr=strcat(unix_cmd,unix_string2);
    system(string_ptr);

    I want the output to UNIX to look like:

    echo $something | cc=`grep -a "ControlID" | cut -c 375-378`

    Then I want $cc passed back to the C program.

    Thanks.

  2. #2
    Registered User
    Join Date
    Oct 2008
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    TX
    Posts
    2,058
    First off get the Unix command right before trying to create one through catenation.

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