iwatch: 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/iwatch - from package: iwatch

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

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