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man Test::Builder::IO::Scalar(3)
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       Test::Builder::IO::Scalar - A copy of IO::Scalar for Test::Builder


       This is a copy of IO::Scalar which ships with Test::Builder to support
       scalar references as filehandles on Perl 5.6.  Newer versions of Perl
       simply use "open()"'s built in support.

       Test::Builder can not have dependencies on other modules without
       careful consideration, so its simply been copied into the distribution.


       This file came from the "IO-stringy" Perl5 toolkit.

       Copyright (c) 1996 by Eryq.  All rights reserved.  Copyright (c)
       1999,2001 by ZeeGee Software Inc.  All rights reserved.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       new [ARGS...]
           Class method.  Return a new, unattached scalar handle.  If any
           arguments are given, they're sent to open().

       open [SCALARREF]
           Instance method.  Open the scalar handle on a new scalar, pointed
           to by SCALARREF.  If no SCALARREF is given, a "private" scalar is
           created to hold the file data.

           Returns the self object on success, undefined on error.

           Instance method.  Is the scalar handle opened on something?

           Instance method.  Disassociate the scalar handle from its
           underlying scalar.  Done automatically on destroy.

   Input and output
           Instance method.  No-op, provided for OO compatibility.

           Instance method.  Return the next character, or undef if none

           Instance method.  Return the next line, or undef on end of string.
           Can safely be called in an array context.  Currently, lines are
           delimited by "\n".

           Instance method.  Get all remaining lines.  It will croak() if
           accidentally called in a scalar context.

       print ARGS...
           Instance method.  Print ARGS to the underlying scalar.

           Warning: this continues to always cause a seek to the end of the
           string, but if you perform seek()s and tell()s, it is still safer
           to explicitly seek-to-end before subsequent print()s.

       read BUF, NBYTES, [OFFSET]
           Instance method.  Read some bytes from the scalar.  Returns the
           number of bytes actually read, 0 on end-of-file, undef on error.

       write BUF, NBYTES, [OFFSET]
           Instance method.  Write some bytes to the scalar.

       sysread BUF, LEN, [OFFSET]
           Instance method.  Read some bytes from the scalar.  Returns the
           number of bytes actually read, 0 on end-of-file, undef on error.

       syswrite BUF, NBYTES, [OFFSET]
           Instance method.  Write some bytes to the scalar.

   Seeking/telling and other attributes
           Instance method.  No-op, provided for OO compatibility.

           Instance method.  No-op, provided for OO compatibility.

           Instance method.  Clear the error and EOF flags.  A no-op.

       eof Instance method.  Are we at end of file?

       seek OFFSET, WHENCE
           Instance method.  Seek to a given position in the stream.

       sysseek OFFSET, WHENCE
           Instance method. Identical to "seek OFFSET, WHENCE", q.v.

           Instance method.  Return the current position in the stream, as a
           numeric offset.

       use_RS [YESNO]
           Instance method.  Deprecated and ignored.  Obey the current setting
           of $/, like IO::Handle does?  Default is false in 1.x, but cold-
           welded true in 2.x and later.

       setpos POS
           Instance method.  Set the current position, using the opaque value
           returned by "getpos()".

           Instance method.  Return the current position in the string, as an
           opaque object.

           Instance method.  Return a reference to the underlying scalar.


       Perl's TIEHANDLE spec was incomplete prior to 5.005_57; it was missing
       support for "seek()", "tell()", and "eof()".  Attempting to use these
       functions with an IO::Scalar will not work prior to 5.005_57.
       IO::Scalar will not have the relevant methods invoked; and even worse,
       this kind of bug can lie dormant for a while.  If you turn warnings on
       (via $^W or "perl -w"), and you see something like this...

           attempt to seek on unopened filehandle

       ...then you are probably trying to use one of these functions on an
       IO::Scalar with an old Perl.  The remedy is to simply use the OO
       version; e.g.:

           $SH->seek(0,0);    ### GOOD: will work on any 5.005
           seek($SH,0,0);     ### WARNING: will only work on 5.005_57 and beyond


       $Id:,v 1.6 2005/02/10 21:21:53 dfs Exp $


   Primary Maintainer
       David F. Skoll (

   Principal author
       Eryq (  President, ZeeGee Software Inc

   Other contributors
       The full set of contributors always includes the folks mentioned in
       "CHANGE LOG" in IO::Stringy.  But just the same, special thanks to the
       following individuals for their invaluable contributions (if I've
       forgotten or misspelled your name, please email me!):

       Andy Glew, for contributing "getc()".

       Brandon Browning, for suggesting "opened()".

       David Richter, for finding and fixing the bug in "PRINTF()".

       Eric L. Brine, for his offset-using read() and write() implementations.

       Richard Jones, for his patches to massively improve the performance of
       "getline()" and add "sysread" and "syswrite".

       B. K. Oxley (binkley), for stringification and inheritance
       improvements, and sundry good ideas.

       Doug Wilson, for the IO::Handle inheritance and automatic tie-ing.


       IO::String, which is quite similar but which was designed more-recently
       and with an IO::Handle-like interface in mind, so you could mix OO- and
       native-filehandle usage without using tied().

       Note: as of version 2.x, these classes all work like their IO::Handle
       counterparts, so we have comparable functionality to IO::String.

perl v5.24.0                      2016-03-01    Test::Builder::IO::Scalar(3pm)

perl 5.24 - Generated Thu Nov 24 14:50:15 CST 2016
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