skipstrip.c

/*
 * Copies every 4th chararacter out of the input string
 * Created to deal with MS Hotmail's problems
 * 2015 The Lightning Stalker
*/

#include <stdio.h>
#include <string.h>

int main (int argc, char **argv)
{
    char *stringin, *stringout;
    int i, j;

    if (argc == 2)
    {
        stringin = argv[1];   // stringin and stringout must be inited
        stringout = stringin; // to strlen(argv[1]) or else segfault!
        j = strlen(stringin) / 4;
        for (i = 0; i <= j; ++i)
        {
            stringout[i] = stringin[i * 4];
        }

        stringout[i] = '\0';
        printf("%s\n", stringout);
    }

    else
    {
        puts("Use like this:");
        printf("%s [string]\n", argv[0]);
        puts("Where [string] is the text to strip every even character.");
    }

    return (0);
}