What is the ruling on a student working in a nightclub (disco) in the profession of hanging clothes and coats due to the lack of other work?

It is not permissible to work in a nightclub in any way whatsoever, due to its involvement in aiding sin, and Allah has forbidden cooperation in sin and aggression. Likewise, it is not permissible to attend those places where Allah is disobeyed. A Muslim must seek sustenance from lawful earnings and trust that Allah will suffice him and provide for him from whence he does not expect if he fears Him and relies on Him.