pcbnew: 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/pcbnew - from package: kicad

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

On Debian possible default full paths are:

/usr/bin/pcbnew - from package: kicad

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

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