uwsgi-core: 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/uwsgi-core - from package: uwsgi-core

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

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