vertex-program-two-side: 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/lib64/piglit/bin/vertex-program-two-side - from package: piglit

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

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