provoking-vertex: 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/provoking-vertex - from package: piglit

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

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