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Full Discussion: Environment Variables
Operating Systems HP-UX Environment Variables Post 302647869 by bakunin on Tuesday 29th of May 2012 03:43:24 AM
Old 05-29-2012
set is used to display the contents of your environment. Issue it and you will get a list of variable=value lines. There are several special variables among these, but it will show you all variables defined in this shell so far.

export is used on variables to have them inherited by processes spawned from this environment.

To explain this in a little more detail: you can start any program from within the shell - even another invokation of this shell. When you declare a variable within a certain shell environment then the program(s) started from this environment does not know about this variable automatically. If the variable is "export"ed it will be known, though.

try the following for yourself:

Code:
# ksh
# x="huhu"
# echo $x
huhu
# ksh               # we start a new environment here
# echo $x           # variable x has no value here, because it was not exported
# exit              # leave the new environment
# echo $x           # we are back in the first one
huhu
# export x
# ksh                # again starting a new environment
# echo $x
huhu
# exit

I hope this helps.

bakunin
 

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set(1F) 							   FMLI Commands							   set(1F)

NAME
set, unset - set and unset local or global environment variables SYNOPSIS
set [-l variable [=value]] ... set [-e variable [=value]] ... set [-ffile variable [=value]]... ... unset -l variable... unset -f file variable... DESCRIPTION
The set command sets variable in the environment, or adds variable=value to file. If variable is not equated it to a value, set expects the value to be on stdin. The unset command removes variable. Note that the FMLI predefined, read-only variables (such as ARG1), may not be set or unset. Note that at least one of the above options must be used for each variable being set or unset. If you set a variable with the -ffilename option, you must thereafter include filename in references to that variable. For example, ${(file)VARIABLE}. FMLI inherits the UNIX environment when invoked. OPTIONS
-l Sets or unsets the specified variable in the local environment. Variables set with -l will not be inherited by processes invoked from FMLI. -e Sets the specified variable in the UNIX environment. Variables set with -e will be inherited by any processes started from FMLI. Note that these variables cannot be unset. -ffile Sets or unsets the specified variable in the global environment. The argument file is the name, or pathname, of a file containing lines of the form variable=value. file will be created if it does not already exist. Note that no space intervenes between -f and file. EXAMPLES
Example 1 A sample output of set command. Storing a selection made in a menu: name=Selection 2 action=`set -l SELECTION=2`close NOTES
Variables set to be available to the UNIX environment (those set using the -e option) can only be set for the current fmli process and the processes it calls. When using the -f option, unless file is unique to the process, other users of FMLI on the same machine will be able to expand these vari- ables, depending on the read/write permissions on file. A variable set in one frame may be referenced or unset in any other frame. This includes local variables. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
env(1), sh(1), attributes(5) SunOS 5.11 5 Jul 1990 set(1F)
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