glx-window-life: 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-window-life - from package: piglit

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

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