my

Shell scripts to easily manage PATH-like environment variables

USAGE

In your shell:

$ my program
Added '/home/user/.opt/program/bin' to PATH
Added '/home/user/.opt/program/lib' to LD_LIBRARY_PATH
Added '/home/user/.opt/program/lib' to LIBRARY_PATH
Added '/home/user/.opt/program/lib/python2.7/site-packages' to PYTHONPATH
Added '/home/user/.opt/program/include' to CPATH
Added '/home/user/.opt/program/share/man' to MANPATH

Use my --silent program to have a silent output.

INSTALL

Create a ~/.opt directory into your home directory and clone this repository as ~/.opt/my.

Similarly, create a subdirectory in ~/.opt for each user program you want to easily manage. Example, for git you would have a ~/.opt/git directory containing a bin and lib directory. The tree would look something like:

$ tree ~/.opt
├── .opt/my
│   ├── bin
│   │   ├── python
│   │   ├── python2 -> python
│   │   ├── python2.0 -> python2
│   │   ├── ...
│   │   ├── python2.7 -> python2
│   │   ├── python3 -> python
│   │   ├── python3.0 -> python3
│   │   ├── ...
│   │   └── python3.5 -> python3
│   ├── my.sh
│   └── README.md
├── .opt/git
│   ├── bin
│   │   ├── git
│   │   └── ...
│   ├── lib
│   │   └── ...
│   ├── lib64
│   │   └── ...
│   ├── libexec
│   │   └── ...
│   └── share
│       ├── locale
│       │   └── ...
│       └── man
│           └── ...
...

Then, do the following, depending on your shell.

Bash

Add source ~/.opt/my.sh in your .bashrc, .bash_profile or .profile.

By default my will look into ~/.opt and /opt directories, you can change that by adding additional search directories to MY_SEARCH_DIRS:

source ~/.opt/my/.sh
MY_SEARCH_DIRS="$MY_SEARCH_DIRS /other/search/path"

Zsh

Not supported yet, but planned.

Others

If you would like your preferred shell to be supported, you are welcome to contribute.

TIPS

When compiling a program, set --prefix=$HOME/.opt/progname (when using configure or setup.py) or -DCMAKE_INSTALL_PREFIX:STRING=$HOME/.opt/progname (when using cmake) when configuring, this will install the program under ~/.opt/progname automatically when running make install.

EXPLANATIONS

Many programs rely on environment variable to find their dependencies. The PATH environment variable is well known, but many forget to also setup LD_LIBRARY_PATH as well, which is required if the programs in PATH use dynamic libraries that are not in the default search path. This script is there to help correctly setting up all those variable.

Here is the description of each variable handled:

• PATH: used by shell(s) and other programs to find binaries, usually under /usr/bin
• LD_LIBRARY_PATH: used by the ld dynamic linker to find dynamic libraries, usually under /usr/lib
• LIBRARY_PATH: used by compilers to find dynamic and static libraries at compile time, usually under /usr/lib
• CPATH: used by C and C++ compilers to find header files at compile time, usually under /usr/include
• PKG_CONFIG_PATH: used by pkg-config to find .pc library descriptor files, usually under /usr/lib/pkgconfig
• MANPATH: used by man to find man pages, usually under /usr/man or /usr/share/man
• PYTHONPATH: used by python to find python packages, usually under /usr/lib/pythonX.Y/site-packages

NOTE: PYTHONPATH is handled differently because its value depends on the python ultimately called (the python version apearing in the PATH). This makes it difficult to handle cases where both python2 and python3 have different set of packages. To handle the problem, my takes care of always having its personal directory first in PATH which contains wrapper script for python. Those wrapper script should catch any call to any version of python thanks to the many symbolic links. Once the call is catched, it will use the actual version of the requested python to correctly setup PYTHONPATH and only then perform the actual call.

NOTE: The reason why my.sh cannot be a binary and must be sourced is that it has to be a shell function to be able to change the environment of the current running shell. The python wrappers, on the other hands, could have been compiled binaries, as they only modify the environment for subprocesses.

KNOWN BUGS

The processing of the options is in the order they appear. my --silent --reset will be silent but my --reset --silent will be verbose.

Options stop being processed after the first directory. my progname --absolute /usr/local will complain about --absolute and /usr/local not beeing found in the search directories.

The python wrappers are not called for script that use the absolute path in the shebang. Please use #!/usr/bin/env python2 instead of #!/usr/bin/python2 so that the interpreter that is used is the one found in PATH. (this advice is valid as well for any other executable script such as sh/bash/perl/ruby/tcl/...)