System monitoring from the command line
Command Line – watch and fswatch
© Lead Image © Shao-Chun Wang, 123RF.com
Two monitoring tools, watch and fswatch, let you gather system information from the command line.
Most users familiar with Linux have probably used cron or at to schedule the running of commands. Both can be useful in their place: cron for repeated scheduling of events and at for scheduling an event once. However, what both lack is the ability to gather system information and respond to it unless you write a specific script. Usually, it is much easier to use watch [1] and fswatch [2] to do both these things. While watch and fswatch can be used simply to gather information or to check for possible security incursions, both can be tweaked to act like a scheduler with little effort and minimal script-writing ability.
watch
The purpose of watch is to follow how a command's output changes over time (Figure 1). This information can be used for troubleshooting, as well as for keeping a root or regular user informed about system changes as new packages are installed or updated. In limited circumstances, it could also be used as a simpler replacement for at or cron. Several other common uses are shown in Table 1. By default, watch runs every two seconds until closed or interrupted. The basic command structure is:
watch OPTIONS COMMAND
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Keep Android Open
Google has announced that, soon, anyone looking to develop Android apps will have to first register centrally with Google.
-
Kernel 7.0 Now in Testing
Linus Torvalds has announced the first Release Candidate (RC) for the 7.x kernel is available for those who want to test it.
-
Introducing matrixOS, an Immutable Gentoo-Based Linux Distro
It was only a matter of time before a developer decided one of the most challenging Linux distributions needed to be immutable.
-
Chaos Comes to KDE in KaOS
KaOS devs are making a major change to the distribution, and it all comes down to one system.
-
New Linux Botnet Discovered
The SSHStalker botnet uses IRC C2 to control systems via legacy Linux kernel exploits.
-
The Next Linux Kernel Turns 7.0
Linus Torvalds has announced that after Linux kernel 6.19, we'll finally reach the 7.0 iteration stage.
-
Linux From Scratch Drops SysVinit Support
LFS will no longer support SysVinit.
-
LibreOffice 26.2 Now Available
With new features, improvements, and bug fixes, LibreOffice 26.2 delivers a modern, polished office suite without compromise.
-
Linux Kernel Project Releases Project Continuity Document
What happens to Linux when there's no Linus? It's a question many of us have asked over the years, and it seems it's also on the minds of the Linux kernel project.
-
Mecha Systems Introduces Linux Handheld
Mecha Systems has revealed its Mecha Comet, a new handheld computer powered by – you guessed it – Linux.