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<HTML> <HEAD> <TITLE>IO::ScalarArray - IO:: interface for reading/writing an array of scalars</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::ScalarArray - IO:: interface for reading/writing an array of scalars </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::ScalarArray - IO:: interface for reading/writing an array of scalars <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::ScalarArray; </PRE> <PRE> # Open a handle on an array-of-scalars: $AH = new IO::ScalarArray; $AH->open(\@a);</PRE> <PRE> # Open a handle on an array-of-scalars, read it line-by-line, # then close it: $AH = new IO::ScalarArray \@a; while ($_ = $AH->getline) { print "Line: $_" } $AH->close;</PRE> <PRE> # Open a handle on an array-of-scalars, and slurp in all the lines: $AH = new IO::ScalarArray \@a; print $AH->getlines;</PRE> <PRE> # Open a handle on an array-of-scalars, and append to it: $AH = new IO::ScalarArray \@a; $AH->print("bar\n"); print "some string is now: ", $somestring, "\n";</PRE> <PRE> # Get the current position: $pos = $AH->getpos; ### $AH->tell() also works</PRE> <PRE> # Set the current position: $AH->setpos($pos); ### $AH->seek(POS,WHENCE) also works</PRE> <PRE> # Open an anonymous temporary scalar array: $AH = new IO::ScalarArray; $AH->print("Hi there!\nHey there!\n"); $AH->print("Ho there!\n"); print "I got: ", @{$AH->aref}, "\n"; ### get at value</PRE> If your Perl is 5.004 or later, you can use the TIEHANDLE interface, and read/write as array-of-scalars just like files: <PRE> use IO::ScalarArray;</PRE> <PRE> # Writing to a scalar array... my @a; tie *OUT, 'IO::ScalarArray', \@a; print OUT "line 1\nline 2\n", "line 3\n"; print "s is now... [", join('', @a), "]\n"; </PRE> <PRE> # Reading and writing an anonymous scalar array... tie *OUT, 'IO::ScalarArray'; 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. For writing large amounts of data with individual <A HREF="../../../lib/Pod/perlfunc.html#item_print"><CODE>print()</CODE></A> statements, this is likely to be more efficient than IO::Scalar. Basically, this: <PRE> my @a; $AH = new IO::ScalarArray \@a; $AH->print("Hel", "lo, "); $AH->print("world!\n");</PRE> Or this (if you have 5.004 or later): <PRE> my @a; $AH = tie *OUT, 'IO::ScalarArray', \@a; print OUT "Hel", "lo, "; print OUT "world!\n";</PRE> Causes @a to be set to the following arrayt of 3 strings: <PRE> ( "Hel" , "lo, " , "world!\n" )</PRE> Compare this with IO::Scalar. <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 array handle. If any arguments are given, they're sent to open(). <DT><A NAME="item_open_%5BARRAYREF%5D">open [ARRAYREF]</A> <DD> Instance method. Open the array handle on a new array, pointed to by ARRAYREF. If no ARRAYREF is given, a ``private'' array 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 array handle opened on something? <DT><A NAME="item_close">close</A> <DD> Instance method. Disassociate the array handle from its underlying array. 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. This does a read(1), which is somewhat costly. <DT><A NAME="item_getline">getline</A> <DD> Instance method. Return the next line, or undef on end of data. 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 array. Currently, this always causes a ``seek to the end of the array'' and generates a new array entry. This may change in the future. <DT><A NAME="item_read_BUF%2C_NBYTES%2C_%5BOFFSET%5D%3B">read BUF, NBYTES, [OFFSET];</A> <DD> Instance method. Read some bytes from the array. 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_eof">eof</A> <DD> Instance method. Are we at end of file? <DT><A NAME="item_seek">seek POS,WHENCE</A> <DD> Instance method. Seek to a given position in the stream. Only a WHENCE of 0 (SEEK_SET) is supported. <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. Seek to a given position in the array, using the opaque <A HREF="#item_getpos"><CODE>getpos()</CODE></A> value. Don't expect this to be a number. <DT><A NAME="item_getpos">getpos</A> <DD> Instance method. Return the current position in the array, as an opaque value. Don't expect this to be a number. <DT><A NAME="item_aref">aref</A> <DD> Instance method. Return a reference to the underlying array. </DL> <HR> <H1><A NAME="version">VERSION</A></H1> $Id: ScalarArray.pm,v 1.112 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 suggesting <A HREF="#item_getc"><CODE>getc()</CODE></A>. Thanks to Brandon Browning for suggesting <A HREF="#item_opened"><CODE>opened()</CODE></A>. <TABLE BORDER=0 CELLPADDING=0 CELLSPACING=0 WIDTH=100%> <TR><TD CLASS=block VALIGN=MIDDLE WIDTH=100% BGCOLOR="#cccccc"> IO::ScalarArray - IO:: interface for reading/writing an array of scalars </TD></TR> </TABLE> </BODY> </HTML>