update-gap-workspace: 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/update-gap-workspace - from package: gap-core

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

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