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

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

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