3 env \- environment variables
15 device serves a one-level directory containing files with arbitrary names
17 The intention is that the file name is the name of an
18 .I environment variable
21 and the content is the variable's current value.
25 system call creates a new process, both the parent and the
26 child continue to see exactly the same files in the
28 device: changes made in either process can be noticed by the other.
35 causes a split: initially both process groups see the
36 same environment files, but any changes made in one process group
37 cannot be noticed by the other.
42 splits and then clears the environment.
44 The special global environment
46 contains kernel configuration variables,
49 All processes see the same
51 its contents are writable only by the host owner.
52 [XXX actually everything is world writable; that's a mistake.]
61 .B /sys/src/9/port/devenv.c
63 A write starting at an offset after the current extent of a file
64 yields an error instead of zero filling.