Probation is when you're not sent to jail or prison so long as you "play by the rules." Those rules (called "terms of probation") often require that you don't commit any more crimes, get and keep a job, and make weekly visits to a probation officer. If you break one of the rules, the sentencing judge can impose the original sentence and send you to jail. Further, it is possible that while your sentence does not mandate you get a job, it could be a term of your probation.

While probation can be revoked for not abiding by terms of probation, it is not an automatic thing, and it is not up to the probation officer to revoke you. If any of the terms of probation are violated, your probation officer can notify the court or prosecutor. The prosecutor may decide to file a complaint asking to have your probation revoked and put you back in jail. If this happens, you'll be served with the complaint and given a date to appear in court to answer it. At this point, you should find a lawyer. If you can't afford a lawyer, one will be appointed for you.

The Court has several options after finding that someone has violated the terms of his probation. The court can impose any sentence that could originally have been imposed for the crime you committed, including jail. The court could also re-sentence you to probation, even on the same terms as before. Or it might re-sentence you to probation but increase the severity of the conditions of your probation, such as putting you in a half-way house, placing you on home detention, enrolling you in an intensive supervision program or requiring you to complete a drug treatment program.

The question presented here is whether the sentencing court would revoke your probation for failure to obtain a job (if that is indeed a term of your probation). It is possible, but doesn't seem likely - especially if you are genuinely trying to obtain employment and can prove that.