strchr.c

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

int main (void)
{
    char extention[] = "this string.css file";
    char* ptr = strchr(extention,'.');
    printf("%s\n",extention);
        char* needle = strrchr(extention,' ');
    char array[needle - ptr + 1];
    strncpy(array,ptr,needle - ptr);


    printf("%s\n",array);
}