Running Commands In Background; Monitoring Status - DEC Digital Alpha VME 4/224 User Manual

>>> ls foo
foo no such file
>>> e 3fff000 -n 1 > foo
>>> ls foo
foo
>>> cat foo
pmem: 3FFF000 0000000000000000
pmem: 3FFF008 0000000000000000
>>> rm foo
>>> ls foo
foo no such file

12.7 Running Commands in Background

''Running a command in background'' means that the console creates a subprocess
to execute the command, leaving the main process available for you to enter a
new command. You can execute any command in the background by placing the
background operator & at the end of the command.
In the following example, three processes are started in the background. The
first process, invoked with the console exer command, reads data from block 0
of a disk. Then, two processes of the console memory test are created, using the
memtest command. In all three cases, the console immediately returns with the
console prompt and awaits further commands.
>>> show device
dka0.2.0.1.0
eza0.0.0.0.0
ezb0.0.0.1.0
pka0.7.0.2.0
>>> exer dka0 -sb 0 -p 0 &
>>> memtest -p 0 &
>>> memtest -p 0 &
>>>

12.7.1 Monitoring Status

The console monitors all the processes while they are executing. To see the status
of all the processes, use the ps command, similar to the OpenVMS show system
command.
To see the status of a specific process, use the grep command with a pipe to filter
the output, as shown at the end of the following example:
# Check to see if foo exists.
# Redirect examine output to file foo.
# Check to see if foo exists.
# Display foo.
# Delete (remove) file foo.
# Check to see if foo exists.
# See what devices are available.
dka0 dka0
EZA0 08-00-2B-1D-02-91
EZB0 08-00-2B-1D-02-92
PKA0 SCSI Bus ID 7
# Read block 0 forever.
# Start up the memory test forever.
# Start up another memory test task.
Console Primer 12–13