shader_runner: 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/shader_runner - from package: piglit

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

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