ref: bdd385803dcbccdf2750f7259a1784744541dec4
dir: /sys/src/games/dmxdec.c/
#include <u.h>
#include <libc.h>
#include <fcall.h>
enum{
Hdrsz = 2+2+4+16,
};
void
main(int argc, char **argv)
{
int n, rate, fd;
uchar buf[Hdrsz], *p;
char fmt[16], len[16];
fd = 0;
if(argc > 1 && (fd = open(argv[1], OREAD)) < 0)
sysfatal("open: %r");
if(read(fd, buf, sizeof buf) != sizeof buf)
sysfatal("short read: %r");
p = buf;
n = GBIT16(p);
if(n != 3) /* format number */
sysfatal("invalid dmx file");
p += 2;
rate = GBIT16(p); /* sample rate (usually 11025Hz) */
p += 2;
n = GBIT32(p);
snprint(fmt, sizeof fmt, "u8c1r%d", rate);
snprint(len, sizeof len, "%d", n);
execl("/bin/audio/pcmconv", "pcmconv", "-i", fmt, "-o", "s16c2r44100", "-l", len, nil);
sysfatal("execl: %r");
}