Tvheadend

In case of an IPTV-URL with pipe and a non-full-qualified-path for ffmpeg-executable it isn't guaranteed that the correct executable is found:

Example:

1. I have the following stream URL:

pipe://ffmpeg -hide_banner -loglevel fatal -i https://zdf-hls-18.akamaized.net/hls/live/2016501/dach/veryhigh/master.m3u8 ...

2. the executable for ffmpeg is located in /usr/bin

$ which ffmpeg
/usr/bin/ffmpeg

3. In /usr/bin there are other executables starting with 'ffmpeg...', i.e.

$ ls -l ffmp*
-rwxr-xr-x 1 root root 301544 Dez 30 12:30 ffmpeg
-rwxr-xr-x 1 root root  22920 Dez 30 12:29 ffmpegthumbnailer

4. I have seen in /var/log/syslog that tvheadend spawns '/usr/bin/ffmpegthumbnailer' instead of '/usr/bin/ffmpeg'

syslog.1:Dec 30 12:53:54 heckies-nuc tvheadend[16726]: spawn: Executing "/usr/bin/ffmpegthumbnailer" 

My guess is that the problem is in spawn.c --> find_exec

/*
 * Search PATH for executable
 */
int
find_exec ( const char *name, char *out, size_t len )
{
  int ret = 0;
  char bin[512];
  char *path, *tmp, *tmp2 = NULL;
  DIR *dir;
  struct dirent *de;
  struct stat st;
  if (name[0] == '/') {
    if (lstat(name, &st)) return 0;
    if (!S_ISREG(st.st_mode) || !(st.st_mode & S_IEXEC)) return 0;
    strlcpy(out, name, len);
    return 1;
  }
  if (!(path = getenv("PATH"))) return 0;
  path = strdup(path);
  tmp  = strtok_r(path, ":", &tmp2);
  while (tmp && !ret) {
    if ((dir = opendir(tmp))) {
      while ((de = readdir(dir))) {
        if (strstr(de->d_name, name) != de->d_name) continue;        // <----- comparison wrong? 
        snprintf(bin, sizeof(bin), "%s/%s", tmp, de->d_name);
        if (lstat(bin, &st)) continue;
        if (!S_ISREG(st.st_mode) || !(st.st_mode & S_IEXEC)) continue;
        strlcpy(out, bin, len);
        ret = 1;
        break;
      }
      closedir(dir);
    }
    tmp = strtok_r(NULL, ":", &tmp2);
  }
  free(path);
  return ret;
}

Workaround is to use full-qualified path like this:

pipe:///usr/bin/ffmpeg -hide_banner -loglevel fatal -i https://zdf-hls-18.akamaized.net/hls/live/2016501/dach/veryhigh/master.m3u8 ...