depth-clamp-status: command not found

Have You tried accessing the binary with the full path?

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/depth-clamp-status - from package: piglit

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