runsvchdir: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/sbin/runsvchdir - from package: runit

You may install the required package with command apt-get install {package}
Error in other languages:
runsvchdir: bevel nie gevind nie
runsvchdir: comandă negăsită
runsvchdir: comando não encontrado
runsvchdir: commande introuvable
runsvchdir: command not found
runsvchdir: käsku ei ole
runsvchdir: không tìm thấy lệnh
runsvchdir: komanda nerasta
runsvchdir: Kommando nicht gefunden.
runsvchdir: kommandot finns inte
runsvchdir: komut yok
runsvchdir: nie znaleziono polecenia
runsvchdir: níor aimsíodh an t-ordú
runsvchdir: no se encontró la orden
runsvchdir: no s'ha trobat l'ordre
runsvchdir: opdracht niet gevonden
runsvchdir: parancs nem található
runsvchdir: perintah tidak ditemukan
runsvchdir: príkaz nenájdený
runsvchdir: příkaz nenalezen
runsvchdir: команда не найдена
runsvchdir: командата не е открита
runsvchdir: 命令找不到
runsvchdir: コマンドが見つかりません