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<HTML> <HEAD> <TITLE>IO::Scalar - IO:: interface for reading/writing a scalar</TITLE> <LINK REL="stylesheet" HREF="../../../Active.css" TYPE="text/css"> <LINK REV="made" HREF="mailto:"> </HEAD> <BODY> <TABLE BORDER=0 CELLPADDING=0 CELLSPACING=0 WIDTH=100%> <TR><TD CLASS=block VALIGN=MIDDLE WIDTH=100% BGCOLOR="#cccccc"> IO::Scalar - IO:: interface for reading/writing a scalar </TD></TR> </TABLE> <A NAME="__index__"></A>  <UL> <LI><A HREF="#name">NAME</A></LI><LI><A HREF="#supportedplatforms">SUPPORTED PLATFORMS</A></LI> <LI><A HREF="#synopsis">SYNOPSIS</A></LI> <LI><A HREF="#description">DESCRIPTION</A></LI> <LI><A HREF="#public interface">PUBLIC INTERFACE</A></LI> <UL> <LI><A HREF="#construction">Construction</A></LI> <LI><A HREF="#input and output">Input and output</A></LI> <LI><A HREF="#seeking and telling">Seeking and telling</A></LI> </UL> <LI><A HREF="#version">VERSION</A></LI> <LI><A HREF="#author">AUTHOR</A></LI> </UL>  <HR> <H1><A NAME="name">NAME</A></H1> IO::Scalar - IO:: interface for reading/writing a scalar <HR> <H1><A NAME="supportedplatforms">SUPPORTED PLATFORMS</A></H1> <UL> <LI>Linux</LI> <LI>Solaris</LI> <LI>Windows</LI> </UL> <HR> <H1><A NAME="synopsis">SYNOPSIS</A></H1> If you have any Perl5, you can use the basic OO interface... <PRE> use IO::Scalar; </PRE> <PRE> # Open a handle on a string: $SH = new IO::Scalar; $SH->open(\$somestring);</PRE> <PRE> # Open a handle on a string, read it line-by-line, then close it: $SH = new IO::Scalar \$somestring; while ($_ = $SH->getline) { print "Line: $_" } $SH->close;</PRE> <PRE> # Open a handle on a string, and slurp in all the lines: $SH = new IO::Scalar \$somestring; print $SH->getlines;</PRE> <PRE> # Open a handle on a string, and append to it: $SH = new IO::Scalar \$somestring $SH->print("bar\n"); ### will add "bar\n" to the end</PRE> <PRE> # Get the current position: $pos = $SH->getpos; ### $SH->tell() also works</PRE> <PRE> # Set the current position: $SH->setpos($pos); ### $SH->seek(POS,WHENCE) also works</PRE> <PRE> # Open an anonymous temporary scalar: $SH = new IO::Scalar; $SH->print("Hi there!"); print "I got: ", ${$SH->sref}, "\n"; ### get at value</PRE> If your Perl is 5.004 or later, you can use the TIEHANDLE interface, and read/write scalars just like files: <PRE> use IO::Scalar;</PRE> <PRE> # Writing to a scalar... my $s; tie *OUT, 'IO::Scalar', \$s; print OUT "line 1\nline 2\n", "line 3\n"; print "s is now... $s\n" </PRE> <PRE> # Reading and writing an anonymous scalar... tie *OUT, 'IO::Scalar'; print OUT "line 1\nline 2\n", "line 3\n"; tied(OUT)->seek(0,0); while (<OUT>) { print "LINE: ", $_ }</PRE> <HR> <H1><A NAME="description">DESCRIPTION</A></H1> This class implements objects which behave just like FileHandle (or IO::Handle) objects, except that you may use them to write to (or read from) scalars. They can be tiehandle'd as well. Basically, this: <PRE> my $s; $SH = new IO::Scalar \$s; $SH->print("Hel", "lo, "); # OO style $SH->print("world!\n"); # ditto</PRE> Or this (if you have 5.004 or later): <PRE> my $s; $SH = tie *OUT, 'IO::Scalar', \$s; print OUT "Hel", "lo, "; # non-OO style print OUT "world!\n"; # ditto</PRE> Or this (if you have 5.004 or later): <PRE> my $s; $SH = IO::Scalar->new_tie(\$s); $SH->print("Hel", "lo, "); # OO style... print $SH "world!\n"; # ...or non-OO style!</PRE> Causes $s to be set to: <PRE> "Hello, world!\n"</PRE> <HR> <H1><A NAME="public interface">PUBLIC INTERFACE</A></H1> <H2><A NAME="construction">Construction</A></H2> <DL> <DT><A NAME="item_new_%5BARGS%2E%2E%2E%5D">new [ARGS...]</A> <DD> Class method. Return a new, unattached scalar handle. If any arguments are given, they're sent to open(). <DT><A NAME="item_open_%5BSCALARREF%5D">open [SCALARREF]</A> <DD> 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. <DT><A NAME="item_opened">opened</A> <DD> Instance method. Is the scalar handle opened on something? <DT><A NAME="item_close">close</A> <DD> Instance method. Disassociate the scalar handle from its underlying scalar. Done automatically on destroy. </DL> <H2><A NAME="input and output">Input and output</A></H2> <DL> <DT><A NAME="item_getc">getc</A> <DD> Instance method. Return the next character, or undef if none remain. <DT><A NAME="item_getline">getline</A> <DD> 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''. <DT><A NAME="item_getlines">getlines</A> <DD> Instance method. Get all remaining lines. It will <CODE>croak()</CODE> if accidentally called in a scalar context. <DT><A NAME="item_print_ARGS%2E%2E%2E">print ARGS...</A> <DD> Instance method. Print ARGS to the underlying scalar. Warning: Currently, this always causes a ``seek to the end of the string''; this may change in the future. <DT><A NAME="item_read_BUF%2C_NBYTES%2C_%5BOFFSET%5D">read BUF, NBYTES, [OFFSET]</A> <DD> Instance method. Read some bytes from the scalar. Returns the number of bytes actually read, 0 on end-of-file, undef on error. </DL> <H2><A NAME="seeking and telling">Seeking and telling</A></H2> <DL> <DT><A NAME="item_clearerr">clearerr</A> <DD> Instance method. Clear the error and EOF flags. A no-op. <DT><A NAME="item_eof">eof</A> <DD> Instance method. Are we at end of file? <DT><A NAME="item_seek">seek OFFSET, WHENCE</A> <DD> Instance method. Seek to a given position in the stream. <DT><A NAME="item_tell">tell</A> <DD> Instance method. Return the current position in the stream, as a numeric offset. <DT><A NAME="item_setpos">setpos POS</A> <DD> Instance method. Set the current position, using the opaque value returned by <A HREF="#item_getpos"><CODE>getpos()</CODE></A>. <DT><A NAME="item_getpos">getpos</A> <DD> Instance method. Return the current position in the string, as an opaque object. <DT><A NAME="item_sref">sref</A> <DD> Instance method. Return a reference to the underlying scalar. </DL> <HR> <H1><A NAME="version">VERSION</A></H1> $Id: Scalar.pm,v 1.114 1998/12/16 02:00:04 eryq Exp $ <HR> <H1><A NAME="author">AUTHOR</A></H1> Eryq (<A HREF="mailto:eryq@zeegee.com">eryq@zeegee.com</A>). President, ZeeGee Software Inc (<A HREF="http://www.zeegee.com">http://www.zeegee.com</A>). Thanks to Andy Glew for contributing <A HREF="#item_getc"><CODE>getc()</CODE></A>. Thanks to Brandon Browning for suggesting <A HREF="#item_opened"><CODE>opened()</CODE></A>. Thanks to David Richter for finding and fixing the bug in <CODE>PRINTF()</CODE>. <TABLE BORDER=0 CELLPADDING=0 CELLSPACING=0 WIDTH=100%> <TR><TD CLASS=block VALIGN=MIDDLE WIDTH=100% BGCOLOR="#cccccc"> IO::Scalar - IO:: interface for reading/writing a scalar </TD></TR> </TABLE> </BODY> </HTML>