Scheduled jobs often will invoke stored procedures on the target server to perform the required function. The following example shows a scheduled job invoking sp_who:
use sybmgmtdb go declare @jobcmd varchar(255), @jobid int select @jobcmd='jcmd=exec sp_who,server=YOUR_SERVER' + ',starttime=' + convert(varchar(32),getdate()) exec @jobid=sp_sjobcreate 'sjname=hello', @jobcmd go
where YOUR_SERVER is the name of your target server.
When Job Scheduler executes a job it prefixes the job text with SQL that creates the job runid and the scheduled job ID. Therefore, the call to sp_who needs to use exec to invoke the stored procedure.