is a very simple software that blocks until all processes with a given name have finished. It basically polls the pid of this process every second (by default, though it can be changed) and, if nothing is captured, the process is considered finished. This may be useful in those situations in which we want the computer to be turned off after a long process has finished while us not being present to do so.
For example, we may want to run a program that makes really long simulations. However, it takes so long that it still needs, say, another two hours to complete just right at the time we would like to go to sleep. We could do so, and leave the computer on until we wake up in the morning and turn it off ourselves, or contiue with our work. However, we don't need to leave the computer on. We could tell the computer to turn itself off after some time, like this:
$ sleep 7200; init 0 # wait two hours and turn off the computer
Of course, this is dangerous. We can never be 100% sure that the simulation actually needs at most two hours to complete. If the init 0 command is called before the simulation has finished we will loose all progress. Therefore, this is not a good solution. Instead, we could have done the following before starting the simulation:
$ sudo su
# ./execute-simulation ; init 0
But this is what we should have done before starting the simulation. Now, it is almost complete and we don't want to start it from the very beginning. So, we decide to use aeo. In another terminal we write:
$ sudo su
# ./aeo -p simulation ; init 0
In this scenario, aeo will block until the simulation finishes, and only after will the init 0 command be invoked.
Needless to say, this is most useful in those situations in which we do not want to create files under sudo, because then we will need administrator permissions to edit those files - and it may be rather tedious to change the permissions on all files created. Also, it is very useful for forgetful people.
The complete usage can be seen using option -h:
$ aeo -h
The interval time used to check the status of the process can also be specified. For example, to use a period of 0.5 seconds:
$ aeo -p apt-get -i 0.5
The order of the options does not matter. The format of the decimal number must conform to the format described in the manual page of the C function: strtod. See https://linux.die.net/man/3/strtod for the documentation.
The operative system must have the utility pidof and have the following headers:
- <sys/resource.h>
- <unistd.h>
- <stdlib.h>
- <string.h>
- <stdio.h>
- <errno.h>
- <math.h>
This software was tested on Ubuntu 14.04 and Ubuntu 16.04.