glsl-uniform-update: 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/glsl-uniform-update - from package: piglit

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

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