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I strongly recommend the 2nd approach, but would change it to <br />
<br />
std::string FilNam &nbsp;= &quot;/var/mail/&quot;;<br />
FilNam += getlogin(); <br />
ifstream in(FilNam.c_str());<br />
<br />
for readability.
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I strongly recommend the 2nd approach, but would change it to

std::string FilNam  = "/var/mail/";
FilNam += getlogin();
ifstream in(FilNam.c_str());

for readability.

<div>
<div class="content wysiwyg-content">
<br />
&nbsp; char* usr = getlogin() ;<br />
&nbsp; ifstream in(&quot;/var/mail/ &nbsp; &lt;output here&gt; &nbsp;&quot;) ;<br />
<br />
I want to substitute the output of getlogin() in the above ifstream, how shoud i, helps please<br />
--begin.<br />

</div>
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  char* usr = getlogin() ;
  ifstream in("/var/mail/   <output here>  ") ;

I want to substitute the output of getlogin() in the above ifstream, how shoud i, helps please
--begin.


string substitution

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