gtst: 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 Debian possible default full paths are:

/usr/lib/debug/usr/bin/gtst - from package: scotch-dbg
/usr/bin/gtst - from package: scotch

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