gerbview: 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/gerbview - from package: kicad

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

On Debian possible default full paths are:

/usr/bin/gerbview - from package: kicad

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

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