roundmode-pixelstore: 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/roundmode-pixelstore - from package: piglit

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