pmcpp: 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/libexec/pcp/bin/pmcpp - from package: pcp

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

On Debian possible default full paths are:

/usr/lib/pcp/bin/pmcpp - from package: pcp

You may install the required package with command apt-get install {package}

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