1IO::Pager::Buffered(3)User Contributed Perl DocumentationIO::Pager::Buffered(3)
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6 IO::Pager::Buffered - Pipe deferred output to PAGER if destination is a
7 TTY
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10 use IO::Pager::Buffered;
11 {
12 local $token = IO::Pager::Buffered::open *STDOUT;
13 print <<" HEREDOC" ;
14 ...
15 A bunch of text later
16 HEREDOC
17 }
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19 {
20 # You can also use scalar filehandles...
21 my $token = IO::Pager::Buffered::open($FH) or warn($!);
22 print $FH "No globs or barewords for us thanks!\n";
23 }
24
25 {
26 # ...or an object interface
27 my $token = new IO::Pager::Buffered;
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29 $token->print("OO shiny...\n");
30 }
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33 IO::Pager subclasses are designed to programmatically decide whether or
34 not to pipe a filehandle's output to a program specified in PAGER;
35 determined and set by IO::Pager at runtime if not yet defined.
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37 This subclass buffers all output for display upon exiting the current
38 scope. If this is not what you want look at another subclass such as
39 IO::Pager::Unbuffered. While probably not common, this may be useful in
40 some cases,such as buffering all output to STDOUT while the process
41 occurs, showing only warnings on STDERR, then displaying the output to
42 STDOUT after. Or alternately letting output to STDOUT slide by and
43 defer warnings for later perusal.
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46 Class-specific method specifics below, others are inherited from
47 IO::Pager.
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49 open( [FILEHANDLE] )
50 Instantiate a new IO::Pager to paginate FILEHANDLE if necessary.
51 Assign the return value to a scoped variable. Output does not occur
52 until all references to this variable are destroyed eg; upon leaving
53 the current scope. See "DESCRIPTION".
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55 new( [FILEHANDLE] )
56 Almost identical to open, except that you will get an IO::Handle back
57 if there's no TTY to allow for IO::Pager agnostic programming.
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59 tell( FILEHANDLE )
60 Returns the size of the buffer in bytes.
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62 flush( FILEHANDLE )
63 Immediately flushes the contents of the buffer.
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65 If the last print did not end with a newline, the text from the
66 preceding newline to the end of the buffer will be flushed but is
67 unlikely to display until a newline is printed and flushed.
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70 If you mix buffered and unbuffered operations the output order is
71 unspecified, and will probably differ for a TTY vs. a file. See
72 perlfunc.
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74 $, is used see perlvar.
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77 IO::Pager, IO::Pager::Unbuffered, IO::Pager::Page,
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80 Jerrad Pierce <jpierce@cpan.org>
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82 Florent Angly <florent.angly@gmail.com>
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84 This module was inspired by Monte Mitzelfelt's IO::Page 0.02
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87 Copyright (C) 2003-2012 Jerrad Pierce
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89 · Thou shalt not claim ownership of unmodified materials.
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91 · Thou shalt not claim whole ownership of modified materials.
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93 · Thou shalt grant the indemnity of the provider of materials.
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95 · Thou shalt use and dispense freely without other restrictions.
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97 Or, if you prefer:
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99 This library is free software; you can redistribute it and/or modify it
100 under the same terms as Perl itself, either Perl version 5.0 or, at
101 your option, any later version of Perl 5 you may have available.
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105perl v5.28.0 2015-02-25 IO::Pager::Buffered(3)