What can go wrong in following code?

#include   
int main(int argc, char *argv[]) {

if(argc != 3) {
        printf("usage: %s [source] [dest]\n", argv[0]);
        exit(1);

    }

    char x;
    FILE *file[2];
    file[0] = fopen(argv[1],"r+");
    file[1] = fopen(argv[2],"w+");
    for(x = 0; x < 2; x++) { 
        if(file[x] == NULL) {
            printf("error opening file.\n");
            exit(1);
        }
    }

    do {
        x = fgetc(file[0]);
        fputc(x,file[1]);
    } while(x != EOF);

     for(x = 0; x < 2; x++)
        fclose(file[x]);
     return 0; 
}