does a child process in PERL has access to Parent process's env variables

Sigh. There ain't no PERL. The language is named Perl, and the executable that reads it is named perl.

No, a child process can not access the environment of the parent, at least not in a portable way (i.e. without playing dirty tricks). Most of the times, the child process inherits a COPY of the environment, but in special cases, the childs environment may be manipulated by the parent before starting the child.

Can Child process change parent process's environment settings in PERL ?

No. This is the same question as before. Allowing that would be dangerous.

I want a child process to run some commands and then change parent process's env settings.

Make perl emit a shell script that can be sourced by the parent shell (after perl has exited) to change its environment. Or even better: Run the entire job from within Perl, so you don't have to mess with any shells.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^3: How to execute commands in the same shell as Perl script by afoken
in thread How to execute commands in the same shell as Perl script by bhagperl

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.