glx-close-display: 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/glx-close-display - from package: piglit

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

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