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There is a difference between userid/groupid and &quot;effective&quot; userid/groupid.<br />
<br />
The effective IDs are only changed with &quot;su -&quot;, and also the login profile of the target user is only executed with &quot;su -&quot;.<br />
<br />
wmp<br />

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There is a difference between userid/groupid and "effective" userid/groupid.

The effective IDs are only changed with "su -", and also the login profile of the target user is only executed with "su -".

wmp


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With su you just become that user but home directory will not be changed and it will not read his .bash_profile and .bashrc so env variable set by him will not be available but<br />
<br />
With su - it is like you have logged in with that user. home directory will be changed. Path will be set according that user. It will read that users .bash_profile and .bashrc, all custome env variable will be available.
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With su you just become that user but home directory will not be changed and it will not read his .bash_profile and .bashrc so env variable set by him will not be available but

With su - it is like you have logged in with that user. home directory will be changed. Path will be set according that user. It will read that users .bash_profile and .bashrc, all custome env variable will be available.

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<div class="content wysiwyg-content">
What is the difference between <br />
<br />

<pre><code id="code-10-26903307-1">su tcn</code></pre>
<br />
and<br />
<br />

<pre><code id="code-10-26903307-2">su - tcn</code></pre>
<br />
I looked up the man page and it states:<br />
<br />

<pre><code id="code-10-26903307-3">Change the effective user id and group id to that of USER.

-, -l, --login</code></pre>
<br />
Doesn't &quot;su tcn&quot; change the user id. &nbsp;Would this command not change the group id without the dash ?<br />

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What is the difference between 

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and

(CODE)

I looked up the man page and it states:

(CODE)

Doesn't "su tcn" change the user id.  Would this command not change the group id without the dash ?


RHEL 6 su command question

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