gdlpp: 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/gdlpp - from package: grcompiler

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

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