1File::RandomAccess(3) User Contributed Perl DocumentationFile::RandomAccess(3)
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NAME

6       File::RandomAccess - Random access reads of sequential file or scalar
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SYNOPSIS

9           use File::RandomAccess;
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11           $raf = new File::RandomAccess(\*FILE, $disableSeekTest);
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13           $raf = new File::RandomAccess(\$data);
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15           $err = $raf->Seek($pos);
16           $num = $raf->Read($buff, $bytes);
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DESCRIPTION

19       Allows random access to sequential file by buffering the file if neces‐
20       sary.  Also allows access to data in memory to be accessed as if it
21       were a file.
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METHODS

24       new Creates a new RandomAccess object given a file reference or refer‐
25           ence to data in memory.
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27               # Read from open file or pipe
28               $raf = new File::RandomAccess(\*FILE);
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30               # Read from data in memory
31               $raf = new File::RandomAccess(\$data);
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33           Inputs:
34               0) Reference to RandomAccess object.
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36               1) File reference or scalar reference.
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38               2) flag set if file is already random access (disables auto‐
39               matic SeekTest).
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41           Returns:
42               Reference to RandomAccess object.
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44       SeekTest
45           Performs test seek() on file to determine if buffering is neces‐
46           sary.  If the seek() fails, then the file is buffered to allow ran‐
47           dom access.  SeekTest() is automatically called from new unless
48           specified.
49
50               $result = $raf->SeekTest();
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52           Inputs:
53               0) Reference to RandomAccess object.
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55           Returns:
56               1 if seek test passed (ie. no buffering required).
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58           Notes:
59               Must be called before any other i/o.
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61       Tell
62           Get current position in file
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64               $pos = $raf->Tell();
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66           Inputs:
67               0) Reference to RandomAccess object.
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69           Returns:
70               Current position in file
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72       Seek
73           Seek to specified position in file.  When buffered, this doesn't
74           quite behave like seek() since it returns success even if you seek
75           outside the limits of the file.
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77               $success = $raf->Seek($pos, 0);
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79           Inputs:
80               0) Reference to RandomAccess object.
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82               1) Position.
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84               2) Whence (0=from start, 1=from cur pos, 2=from end).
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86           Returns:
87               1 on success, 0 otherwise
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89       Read
90           Read data from the file.
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92               $num = $raf->Read($buff, 1024);
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94           Inputs:
95               0) Reference to RandomAccess object.
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97               1) Buffer.
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99               2) Number of bytes to read.
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101           Returns:
102               Number of bytes actually read.
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104       ReadLine
105           Read a line from file (end of line is $/).
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107           Inputs:
108               0) Reference to RandomAccess object.
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110               1) Buffer.
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112           Returns:
113               Number of bytes read.
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115       Slurp
116           Read whole file into buffer, without changing read pointer.
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118           Inputs:
119               0) Reference to RandomAccess object.
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121           Returns:
122               Nothing.
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124       BinMode
125           Set binary mode for file.
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127           Inputs:
128               0) Reference to RandomAccess object.
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130           Returns:
131               Nothing.
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133       Close
134           Close the file and free the buffer.
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136           Inputs:
137               0) Reference to RandomAccess object.
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139           Returns:
140               Nothing.
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AUTHOR

143       Copyright 2004-2006 Phil Harvey (phil at owl.phy.queensu.ca)
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145       This library is free software; you can redistribute it and/or modify it
146       under the same terms as Perl itself.
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SEE ALSO

149       Image::ExifTool(3pm)
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153perl v5.8.8                       2007-09-12             File::RandomAccess(3)