sysenv

This utility makes you quite easy to manage your environment variables.

---

NOTE:

• This utility works with bash only!
• env-mpi-select is not finished yet!

Installation

1. git clone to your local disk.

Suppose it's cloned to /sysenv. The cloned directory should be readable by everyone.

2. Integrate sysenv into bash.

Just run

sudo python /sysenv/install.py

A line of source /sysenv/env.bashrc will be added to the proper file.

• For Ubuntu: Added to the top of /etc/bash.bashrc
• For CentOS: Added to the top of /etc/bashrc
• For other OS: The installer can't do it for you. Manually add the above line into your system-wide bash profile.

NOTE:

• /sysenv/env.bashrc is sourced no matter bash is interactive or not.
• /sysenv/env.bashrc is sourced even if bash is started by SSH.
• Idempotence: to source /sysenv/env.bashrc many times is OK.

Usage

1. Use ~/env.conf to define environment variables.

It's quite easy to define environment variables using ~/env.conf

env.conf has a simple ini-style syntax:

• Multiple values of an environment variable is defined in multiple lines, they will be joined with colon : at last
• To reference environment variables (bash-style syntax: $VAR or ${VAR}) when defining a environment variable is permitted
• "Internal" variables (starting with dot .) will not be exported, but they bring convenience
• Using special characters in environment variables is OK

Please see env.conf.example for details.

2. Bash Command: env-reload

env-reload

After changing your ~/env.conf, use this command to reload the file.

Quite a few corner cases are considered and tests, feel safe and free to use this command!

The effect is real-time, which means you DO NOT need to exit & restart your bash

3. Bash Command: env-mpi-select

env-mpi-select              # This will show the information
env-mpi-select <target>     # This will switch to the target implementation

Use env-mpi-select to switch to a different MPI implementation.

The effect is real-time, which means you DO NOT need to exit & restart your bash

Warning

NOT every corner cases are tested. So please take care when using any strange characters in path string.

For example:

• Colons :

Back slashes \, Dollars (escaped) $$, Whitespaces , single quotes ' and double quotes " should work.

However, it's still strongly suggested NOT including these characters in path string, since not every program and library handles them very well.

Similar Tools

I found there are some similar tools, but they are not light-weight enough.

SoftEnv

See http://www.mcs.anl.gov/hs/software/systems/softenv/softenv-intro.html

Environment Modules

See http://modules.sourceforge.net/

Example ~/env.conf

###############################################################################
# Add your personal $PATH here
###############################################################################
[PATH]
/your/path1/bin
/your/path2/bin
/your/path3/bin


###############################################################################
# The following lines demonstrate how variant expansion works.
# Generally speaking, it's a cartesian product.
#
# With
#   FOO=ab:cd
#   BAR=123:456
# We have
#   $FOO$BAR=ab123:ab456:
###############################################################################
[FOO]
ab
cd

[BAR]
123
456

# DUMMY will be "ab123-xyz:ab456-xyz:cd123-xyz:cd456-xyz:ab233:cd233"
[DUMMY]
$FOO$BAR-xyz
${FOO}233


###############################################################################
# Use '$$' to escape a '$' character.
# Special characters are OK in the values, like:
# single quotes, double quotes, whitespaces, bask-slashes...
#
# In the following example, MY_VAR =
#   M\y$V:a "lu'e"
###############################################################################
[MY_VAR]
M\y$$V:a "lu'e"


###############################################################################
# Make it easy to set environment variables:
# - Multiple names in the same "[" "]" separated by whitespaces will be
#     assigned the same value
# - Dot-started names will NOT be exported, but they can be referenced in
#     other variables (for convenience)
#
# The following statements make it easy to add your self-compiled library's
#   paths into environment variables: LIBRARY_PATH, C_INCLUDE_PATH &
#   CPLUS_INCLUDE_PATH for compilers; PATH & LD_LIBRARY_PATH for executables,
#   MANPATH for man-documentation, PKG_CONFIG_PATH for pkg-config.
# If you place all your compiled library in the same root directory (NOT the
#   same "--prefix" option!), like ~/build, it's quite convenient to write
#   like the following. Now if you want to compile openssl, just run
#     ./configure --prefix=$HOME/build/libssl <other_options>
#     make && make install
#   and uncomment the libssl line below. Then run 'env-reload' - All done.
#
# As you have this tool, please DO NOT:
#   - Compile many libraries/executables with the same "--prefix" option
#   - Compile a library/executable with default option "--prefix" = /usr/local
#
###############################################################################

[.my_compiled_libs]
libpcre
libhmsbeagle
#libssl

[.my_install_root]
~/build/${.my_compiled_libs}
/usr/local/cuda-8.0

[LIBRARY_PATH LD_LIBRARY_PATH]
${.my_install_root}/lib
${.my_install_root}/lib64

[PKG_CONFIG_PATH]
${.my_install_root}/lib/pkgconfig

[C_INCLUDE_PATH CPLUS_INCLUDE_PATH]
${.my_install_root}/include

[MANPATH]
${.my_install_root}/share/man

[PATH]
${.my_install_root}/bin