phpcov: 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/bin/phpcov - from package: php-phpunit-phpcov

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

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