Change the "L2SD" (used for some reason on lineage 2 music files) to "OggS" on .ogg files. Making it recognizable to common audio players.

convertl2ogg.c

#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main (int argc, char *argv[]) {
	if (argc == 1){
		printf("Usage: convertl2ogg [DIRECTORY]\n");
	}
	DIR* dir = opendir(argv[1]);
	if (dir) {
		int file_no = 0;
		struct dirent *entry;
		FILE *file;
		char check[4];
		while ((entry=readdir(dir))){
			file = fopen(entry->d_name, "r+b");
			if(file){
				fread(check, 1, 4, file);
				if ((strcmp(check, "L2SD")) == 0){
					fseek(file, 0, SEEK_SET);
					fwrite("OggS", sizeof(char), 4, file);
					file_no++;
				}
				fclose(file);
			}
		}
		printf("%d files changed\n", file_no);
		closedir(dir);
	} else if (ENOENT == errno) {
		printf("Error: %d\n", errno);
	} else {
		printf("Unknown error\n");
	}
}