Hi
Maybe no active jobs. From Man sh
jobs [-lnp] [job]...
List information about each given job, or all active jobs if job
is not specified. With -l, list process IDs in addition to the
normal information. With -n, display only jobs that have stopped
or exited since last notified. With -p, list only the process
group. See the "Jobs" subsection for a description of the format
of job.
Jobs
If the monitor option of the set command is turned on, an interactive
shell associates a job with each pipeline. It keeps a table of
current jobs, printed by the jobs command, and assigns them small
integer numbers. When a job is started asynchronously with &, the
shell prints a line that looks like:
[1] 1234
indicating that job number 1 was started asynchronously and had one
(top-level) process whose process ID was 1234.
If you are running a job and wish to do something else, you can type
the suspend character (the susp character defined with stty; see
stty(1)) to send a SIGSTOP signal to the current job. The shell then
indicates that the job has been Stopped, and prints another prompt.
Then you can manipulate the state of this job by putting it in the
background with the bg command, running other commands, and eventually
returning the job to the foreground with the fg command. A suspend
takes effect immediately and resembles an interrupt, since pending
output and unread input are discarded when the suspend is entered.
Steve Steel
If you want truly to understand something, try to change it. (Kurt Lewin)
