NAME
env2 - Converts environment variables to various script languages.
SYNOPSIS
env2 -from *SHELL* -to *SHELL* [-o *DESTINATION_FILE*] *SOURCE_FILE*
env2 --save [FILE]
env2 # displays help
DESCRIPTION
Do you prefer running bash while the rest of the team runs tcsh? Or
perhaps you learned csh and the system administrators only know ksh.
What happens when they (or you) supply an initialization script to
source? If any of these situations sounds familiar, then this may be the
script for you.
env2 takes shell scripts of one flavor in and spits out scripts
effectively equivalent in another dialect. We say "effectively
equivalent" because it does not translate syntax such as if/else
statements. Instead, the original (source) script is evaluated to
determine what environment variables it modifies, and the effective
values of those variables are simply expressed in the syntax of the
destination script's dialect. Typically, this is all you really need for
scripts that modify the environment.
NOTE: If you need to the conditionals and for-loops to be used for
different situations (e.g. different host architectures), then simply
use this script repeatedly as needed.
Future extensions may include aliases or <functions>. Supported
languages currently include: bash, csh, ksh, modulecmd, perl, plist, sh,
tclsh, tcsh, vim, yaml, and zsh.
NOTE: The file version is identified by an internally computed SHA1 hash
similar to the way git does versioning. If you get a warning message
about inconsistent hash, it means that somebody modified the file
without updating the $SHA variable.
OPTIONS
-all
Include all variables rather than just those that changed. See
-diff.
-clear
Resets the ignore list to almost completely empty except for the
generally dangerous environment list.
See -ignore, -reset, and -unsafe_clear.
-diff
Only include those variables whose values are different as a result
of sourcing the specified input script. This is the default action.
-from DIALECT
The dialect to translate from. If not present, then the input file
is examined for a #! line. If that fails, the SHELL environment
variable is examined. If that fails, we default to bash (Hey, I had
to choose something, and bash is the default Linux shell of choice).
-help
This built-in documentation. Written in POD so that you can also
have it in HTML, PDF, RTF, plain text or as a man page.
-ignore VARLIST
Comma separated list of variables to ignore. By default, env2 starts
with the list set to
_,ENV,ENV2,OLDPWD,SHLVL
See also -clear, -reset and -unsafe_clear.
-ignored
Lists variables that will be ignored. Useful if you are uncertain
and want to clarify things before proceeding.
-o [*FILE*]
Specifies a *FILE* to save the results in. By default results are
sent to STDOUT. If you leave off the *FILE*, the filename will be
"env2."$SHELL.
-profile [*FILE*]
Specifies a file that contains the starting environment. Defaults to
".env2profile". Searches for the file in the current directory or
$HOME if path not specified.
-reset
Resets the ignore list to a minimum set.
See also -clear, -ignore and -unsafe_clear.
-save [FILE]
Saves the environment in a perl format. By default saves to env2.pl.
Internally, this option is invoked as part of the conversion process
and saves an intermediate file to /tmp/env2.$$.pl.
-sha1
Displays the SHA1 version identifier. Use this to see if script has
been modified since last updated.
-to DIALECT
The dialect to translate to. If not supplied, the SHELL environment
variable is examined. If that fails, we default to bash (Hey, I had
to choose something, and bash is the default Linux shell of choice).
-uniq *[PATHLIST]*
Ensure that each path variable specified in *PATHLIST* contains a
unique colon separated list. Default is to apply this to common path
variables:
MANPATH
PATH
LD_LIBRARY_PATH
DYLD_LIBRARY_PATH
PERL5LIB
-unsafe_clear
Resets the ignore list to completely empty. This is potentially
dangerous because allows inclusion of dangerous environment
variables that the user should not touch. These dangerous variables
can have an adverse affect on operation of UNIX.
See also -clear, -ignore and -reset.
--version
Display version of script.
ENVIRONMENT
ENV2 environment variable contains default command-line arguments if
defined.
DEPENDENCIES
To support YAML, this script uses the CPAN YAML module.
EXAMPLES
# Simple conversion
env2 -from ksh -to csh -o setup.csh setup.ksh
# Create a modules cmd for a new xyz tool version 1.0
TOOL_SETUP=$TOOLS/vendor_dir/xyz_tool/xyz-1.0/setup.script
MDLDIR=$TOOLS/modules/tools/xyz
env2 -from sh -to modulecmd -o $MDLDIR/1.0 $TOOL_SETUP
# Dynamically use a script for another shell to set environment
eval `env2 -from ksh -to $SHELL -o setup.csh setup.ksh`
COPYRIGHT/LICENSE
env2 is copyright (C) 2003-2008 David C Black. All rights reserved. This
code may is hereby made available under Apache 2.0 licensing.
AUTHOR
David C. Black <dcblack@hldwizard.com>
