swift-form-signature: 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 Debian possible default full paths are:

/usr/bin/swift-form-signature - from package: swift

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

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