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Sinoosh
Asked: 2016-10-18 05:01:14 +0800 CST

What's the difference between "export -p" and "env" commands?

  • 772

env displays a list of all environment variables

$ env |wc -l
63

Total environment variables = 63

According to help export 

-p   display a list of all exported variables and functions

$export -p |wc -l 
63

Environment variables+lines of functions=63 then lines of functions=0

set disply a list of environment variables+ shell variables+functions 

$set |wc -l
4772

Then for showing only variables(environment variables+shell variables)

$(set -o posix ;set)|wc -l
172

It means lines of functions= 4772-172 not zero please explain to me what's happening?

command-line

1 Answers

  1. Best Answer

    The confusion arises from the fact that export -p by default only shows exported variables (declare -x), not functions.

    To display the exported functions (declare -fx) using export:

    export -fp

    Also just to clarify, counting number of lines to get number of functions is completely wrong as function definitions span multiple lines (even if it defined in a single line while declaring, set shows them in multiple lines).

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