sunflow: command not found

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/bin/sunflow - from package: sunflow

You may install the required package with command apt-get install {package}

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