rotctld: 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/rotctld - from package: hamlib

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

On Debian possible default full paths are:

/usr/bin/rotctld - from package: libhamlib-utils

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

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