insn_write: 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/insn_write - from package: xenomai-runtime

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

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