PROC(5) Linux Programmer's Manual PROC(5)
proc - process information pseudo-file system
The proc file system is a pseudo-file system which is used as an interface to kernel data structures. It is commonly mounted at /proc.
Most of it is read-only, but some files allow kernel variables to be changed.
The following outline gives a quick tour through the /proc hierarchy.
There is a numerical subdirectory for each running process; the subdirectory is named by the process ID. Each such subdirectory
contains the following pseudo-files and directories.
/proc/[pid]/auxv (since 2.6.0-test7)
This contains the contents of the ELF interpreter information passed to the process at exec time. The format is one unsigned long
ID plus one unsigned long value for each entry. The last entry contains two zeros.
This holds the complete command line for the process, unless the process is a zombie. In the latter case, there is nothing in this
file: that is, a read on this file will return 0 characters. The command-line arguments appear in this file as a set of null-sepa-
rated strings, with a further null byte ('