testcover: 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/testcover - from package: perl-ExtUtils-MakeMaker-Coverage

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

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