select: 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/select - from package: piglit

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

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