cppo: 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 CentOS possible default full paths are:

/usr/bin/cppo - from package: ocaml-cppo

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/cppo - from package: cppo

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

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