gnudoit: command not found

Have You tried accessing the binary with the full path?

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/gnudoit - from package: xemacs

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