gl-1.0-edgeflag-const: 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/gl-1.0-edgeflag-const - from package: piglit

You may install the required package with command yum install {package}
Error in other languages:
gl-1.0-edgeflag-const: bevel nie gevind nie
gl-1.0-edgeflag-const: comandă negăsită
gl-1.0-edgeflag-const: comando não encontrado
gl-1.0-edgeflag-const: commande introuvable
gl-1.0-edgeflag-const: command not found
gl-1.0-edgeflag-const: käsku ei ole
gl-1.0-edgeflag-const: không tìm thấy lệnh
gl-1.0-edgeflag-const: komanda nerasta
gl-1.0-edgeflag-const: Kommando nicht gefunden.
gl-1.0-edgeflag-const: kommandot finns inte
gl-1.0-edgeflag-const: komut yok
gl-1.0-edgeflag-const: nie znaleziono polecenia
gl-1.0-edgeflag-const: níor aimsíodh an t-ordú
gl-1.0-edgeflag-const: no se encontró la orden
gl-1.0-edgeflag-const: no s'ha trobat l'ordre
gl-1.0-edgeflag-const: opdracht niet gevonden
gl-1.0-edgeflag-const: parancs nem található
gl-1.0-edgeflag-const: perintah tidak ditemukan
gl-1.0-edgeflag-const: príkaz nenájdený
gl-1.0-edgeflag-const: příkaz nenalezen
gl-1.0-edgeflag-const: команда не найдена
gl-1.0-edgeflag-const: командата не е открита
gl-1.0-edgeflag-const: 命令找不到
gl-1.0-edgeflag-const: コマンドが見つかりません