gl-functions: 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/share/drbl/setup/files/gparted/usr/share/gparted/bin/gl-functions - from package: clonezilla

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

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