This subchapter looks at free, a Linux command.
free is used to show free memory.
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This subchapter looks at free, a Linux only command.
free displays the total amount of free and used physical memory and swap space in the system, as well as the buffers and cache consumed by the kernel.
The default is to report the memory size in bytes. Use the -g option to display in Gigabytes. Use the -m option to display in Megabytes. Use the -k option to display in Kilobytes. Use the -b option to display in Bytes.
Use the -t option to view total memory.
Use the -l option to view low vs. high memory usage.
The default is to display the information once and then return to the normal shell. Use the -s n option (where n is the number of times to display) to keep displaying the memory usage (until interrupted). Use the -c n or --count=n options (where n is the number of times to display the memory statistics).
Use the Activity Monitor for this purpose. From the command line, you can get similar results from vm_stat. vm_stat is a Mach-specific version of the UNIX command vmstat Also:
$ echo -e "\n$(top -l 1 | awk '/PhysMem/';)\n"
On November 8, 2010, Ramesh Natarajan named this the number 23 most frequently used UNIX/Linux command at this web page 50 Most Frequently Used UNIX / Linux Commands (With Examples).
Coding example: I am making heavily documented and explained open source code for a method to play music for free — almost any song, no subscription fees, no download costs, no advertisements, all completely legal. This is done by building a front-end to YouTube (which checks the copyright permissions for you).
View music player in action: www.musicinpublic.com/.
Create your own copy from the original source code/ (presented for learning programming).
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Teach Yourself UNIX/Linux System Administration and Shell Programming
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This web site handcrafted on Macintosh computers using Tom Bender’s Tex-Edit Plus and served using FreeBSD .
†UNIX used as a generic term unless specifically used as a trademark (such as in the phrase “UNIX certified”). UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.
Names and logos of various OSs are trademarks of their respective owners.
Copyright © 2012 Milo
Created: February 2, 2012
Last Updated: July 10, 2012
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