xdpr: 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/xdpr - from package: xorg-x11-apps

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

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