ekg-ncurses: 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/ekg-ncurses - from package: ekg

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

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