typedef union inspector_u {
    char  chararray [16];
    int   inspectint;
    short inspectshort;
    long  inspectlong;
}   inspector_t;

int  main ( int aAc, char ** aAv ) {
    inspector_t inspector;

    // Why not just simple assign ?
    memset( &inspector, 0, sizeof( inspector ) ); 

    // Why just -1 ?
    inspector.inspectint = -1;

    // Here comes the code that checks the chararray
    // figure it out Yourself.

    return 0;
}