#include <stdio.h>
#include <stdlib.h>
#include "h.h"
BP bp; note * mus = 0;
int main(int argc, char * * argv){note * music = Read("", &bp);
if(argc < 5) {printf("%s old-trk-num old-chn-num new-trk-num new-chn-num"
    " < MIDI-file-name\n", argv[0]); exit(0);}
int ot = atoi(argv[1]), oc = atoi(argv[2]), nt = atoi(argv[3]), nc = atoi(argv[4]);
printf("Changing channel %d in track %d to channel %d in track %d.\n"
  " Output to file out.midi\n", oc, ot, nc, nt);

{void fed(note n){
    if(n.trk == ot && n.chan == oc){n.trk = nt; n.chan = nc;}
    aug(n, &mus);}
scan(fed, music, 1);}
Write("", mus, &bp); return 0;}