use FileHandle::Rollback; my $INDEXFILE_M; $INDEXFILE_M=&abc(); $INDEXFILE_M->commit();#error sub abc{ my $INDEXFILE = FileHandle::Rollback->new("< a.txt") or die "cannot op +en filehandle: $!"; select($INDEXFILE); print "AAAA"; return \*$INDEXFILE; }
I use FileHandle::Rollback to read and write file,because of its function of rollback. Now I want to let a sub return the obj(FileHandle::Rollback) refference, and I can call commit() in main sub. but it seems cannot run. abc sub can return a filehandle but can not call commit(),why is it? error message Can't call method "commit" on an undefined value at D:/Program Files/perl/site/lib/FileHandle/Rollback.pm line 188. at D:/Program Files/perl/site/lib/FileHandle/Rollback.pm line 188 FileHandle::Rollback::commit('FileHandle::Rollback=GLOB(0x1df63e4)') called at D:/HF_project_perl/V3.0/darft.pl line 8

In reply to Is it a filehandle or a obj refference? by jiwei800715

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.