xref: /inferno-os/man/3/env (revision 46439007cf417cbd9ac8049bb4122c890097a0fa)
ENV 3
NAME
env - environment device
SYNOPSIS
 bind #e /env 
 /env/ name 
DESCRIPTION
The environment device serves a one-level directory giving access to environment variables and their values. It is conventionally bound to /env . The value of an environment variable name may be obtained by reading the file /env/ name. If the file does not exist, the variable is unset and has the value nil. The maximum length of a variable name is 127 bytes.

New environment variables are set by creating the corresponding file in /env and writing the required value to that file. Similarly environment variables are destroyed (unset) by removing the corresponding file.

Processes sharing an `environment group' see the same files and contents; changes made by one process are seen by the others. A process can insulate itself from further changes using the .L FORKENV option to sys-pctl (2), which creates a new environment group that is a copy of the old, but further changes in each are independent. A new empty environment group is created by the .L NEWENV option to sys-pctl (2).

SOURCE
/os/port/devenv.c

/emu/port/devenv.c

SEE ALSO
env (1), sh (1), env (2), sys-pctl (2)