IO::File(3pm)

1IO::File(3pm)          Perl Programmers Reference Guide          IO::File(3pm)
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NAME

6       IO::File - supply object methods for filehandles
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SYNOPSIS

9           use IO::File;
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11           $fh = new IO::File;
12           if ($fh->open("< file")) {
13               print <$fh>;
14               $fh->close;
15           }
16
17           $fh = new IO::File "> file";
18           if (defined $fh) {
19               print $fh "bar\n";
20               $fh->close;
21           }
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23           $fh = new IO::File "file", "r";
24           if (defined $fh) {
25               print <$fh>;
26               undef $fh;       # automatically closes the file
27           }
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29           $fh = new IO::File "file", O_WRONLY⎪O_APPEND;
30           if (defined $fh) {
31               print $fh "corge\n";
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33               $pos = $fh->getpos;
34               $fh->setpos($pos);
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36               undef $fh;       # automatically closes the file
37           }
38
39           autoflush STDOUT 1;
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DESCRIPTION

42       "IO::File" inherits from "IO::Handle" and "IO::Seekable". It extends
43       these classes with methods that are specific to file handles.
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CONSTRUCTOR

46       new ( FILENAME [,MODE [,PERMS]] )
47           Creates an "IO::File".  If it receives any parameters, they are
48           passed to the method "open"; if the open fails, the object is
49           destroyed.  Otherwise, it is returned to the caller.
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51       new_tmpfile
52           Creates an "IO::File" opened for read/write on a newly created tem‐
53           porary file.  On systems where this is possible, the temporary file
54           is anonymous (i.e. it is unlinked after creation, but held open).
55           If the temporary file cannot be created or opened, the "IO::File"
56           object is destroyed.  Otherwise, it is returned to the caller.
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METHODS

59       open( FILENAME [,MODE [,PERMS]] )
60       open( FILENAME, IOLAYERS )
61           "open" accepts one, two or three parameters.  With one parameter,
62           it is just a front end for the built-in "open" function.  With two
63           or three parameters, the first parameter is a filename that may
64           include whitespace or other special characters, and the second
65           parameter is the open mode, optionally followed by a file permis‐
66           sion value.
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68           If "IO::File::open" receives a Perl mode string (">", "+<", etc.)
69           or an ANSI C fopen() mode string ("w", "r+", etc.), it uses the
70           basic Perl "open" operator (but protects any special characters).
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72           If "IO::File::open" is given a numeric mode, it passes that mode
73           and the optional permissions value to the Perl "sysopen" operator.
74           The permissions default to 0666.
75
76           If "IO::File::open" is given a mode that includes the ":" charac‐
77           ter, it passes all the three arguments to the three-argument "open"
78           operator.
79
80           For convenience, "IO::File" exports the O_XXX constants from the
81           Fcntl module, if this module is available.
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83       binmode( [LAYER] )
84           "binmode" sets "binmode" on the underlying "IO" object, as docu‐
85           mented in "perldoc -f binmode".
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87           "binmode" accepts one optional parameter, which is the layer to be
88           passed on to the "binmode" call.
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NOTE

91       Some operating systems may perform  "IO::File::new()" or
92       "IO::File::open()" on a directory without errors.  This behavior is not
93       portable and not suggested for use.  Using "opendir()" and "readdir()"
94       or "IO::Dir" are suggested instead.
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HISTORY

100       Derived from FileHandle.pm by Graham Barr <gbarr@pobox.com>.
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104perl v5.8.8                       2001-09-21                     IO::File(3pm)