#BASH RETURN PROC CPUINFO DRIVERS#
#BASH RETURN PROC CPUINFO DRIVER#
#BASH RETURN PROC CPUINFO CODE#
#BASH RETURN PROC CPUINFO DOWNLOAD#

You can see that the code is pretty much boilerplate code: since most files under /proc just dump some text data, there are helper functions to do that. Taking /proc/cpuinfo as an example, a search for 'cpuinfo' leads you to the call to proc_create('cpuinfo, …') in fs/proc/cpuinfo.c. Kernel versions up to 3.9 provide the functions create_proc_entry and some wrappers (especially create_proc_read_entry), and kernel versions 3.10 and above provide instead only proc_create and proc_create_data (and a few more).

#BASH RETURN PROC CPUINFO DRIVERS#

Drivers call functions declared in include/linux/proc_fs.h.

#BASH RETURN PROC CPUINFO DRIVER#

Any driver can register entries in /proc (though as indicated above this is now deprecated in favor of /sys), so if you don't find what you're looking for in fs/proc, look everywhere else. The core handling of /proc entries is in the fs/proc directory. (There are many variants of LXR the one running on is the nicest by far but unfortunately the site is often down.) A little knowledge of C is required, but you don't need to be a programmer to track down a mysterious value.

#BASH RETURN PROC CPUINFO DOWNLOAD#

You can download the source on your machine, but this is a huge program, and LXR, the Linux cross-reference, is a big help. Your third entry point, when the documentation doesn't cover it, is reading the source.

The /proc filesystem in the kernel documentation.

Your first and second entry points for documentation about /proc on Linux are: Entries like /proc/bus and /proc/fs/ext4 remain where they are for backward compatibility, but newer similar interfaces are created under /sys. In the past, Linux's /proc acquired various files that provide information about drivers, but this use is now deprecated in favor of /sys, and /proc now evolves slowly. Linux extends the proc filesystem with many more entries that report the state of the system, including your example /proc/cpuinfo. Most procfs implementations have a file or directory called /proc/123 to report information about the process with PID 123. It started its life in AT&T's Bell Labs in UNIX 8th edition as a way to report information about processes (and ps is often a pretty-printer for information read through /proc). Procfs is present in most non-BSD unices. Unlike usual filesystems, the filesystem which is mounted on /proc, which is called procfs, doesn't load data from a disk or other storage media (like FAT, ext2, zfs, …) or over the network (like NFS, Samba, …) and doesn't call user code (unlike FUSE). The fact that the content is generated on the fly explains why almost all files have their time reported as now and their size reported as 0 - here you should read 0 as “don't know”.

flags – Defines a number of different processor attributes, such as the presence of a floating-point unit (FPU) and the ability to process MMX instructions.Whenever you read a file under /proc, this invokes some code in the kernel which computes the text to read as the file content.

cache size – Tells you the amount of level 2 memory cache available to the processor.

cpu MHz – Shows the processor’s precise speed, in megahertz, to the thousandth decimal point.

model name – Gives you the common name of the processor, including the project name.

This is helpful to determine the type of architecture of an older system and is helpful in determining which compiled RPM package would best suit that system.

If your computer is an Intel-based system, simply place the number in front of “86” to determine the value. cpu family – Authoritatively tells you the type of processor you have in the system.If you have more than one processor it will display all processor information separately counting the processors using zero notation. If you have one processor it will display a 0.

processor – Provides each processor with an identifying number.

Model name : Intel(R) Xeon(R) CPU E5-2660 0 2.20GHzįlags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid xsaveoptĪddress sizes : 46 bits physical, 48 bits virtualīelow is the various items you would see in the output and their respective explanations.

Bash return proc cpuinfo