3.1.1. Viewing Virtual Files

3.1.1. Viewing Virtual Files

By using the cat, more, or less commands on files within the /proc/ directory, users can immediately access enormous amounts of information about the system. For example, to display the type of CPU a computer has, type cat /proc/cpuinfo to receive output similar to the following:

processor : 0 vendor_id : AuthenticAMD cpu family : 5 model : 9 model name : AMD-K6(tm) 3D+ Processor stepping : 1 cpu MHz : 400.919 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr mce cx8 pge mmx syscall 3dnow k6_mtrr bogomips : 799.53

When viewing different virtual files in the /proc/ file system, some of the information is easily understandable while some is not human-readable. This is in part why utilities exist to pull data from virtual files and display it in a useful way. Examples of these utilities include lspci, apm, free, and top.

Note

Some of the virtual files in the /proc/ directory are readable only by the root user.


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