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Perl in a Nutshell

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Standard Modules
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8.92 IO::Handle

The base class for all other IO handle classes. Its main purpose is for the other IO classes to inherit from it; programs should not create IO::Handle objects directly. Provides the following methods:

IO::Handle also provides the following methods, which are not described in detail here because they are simply front-ends for the corresponding built-in functions. See Chapter 5, Function Reference, for more information.

closeCloses file or pipe
eofReturns 1 if next read will return end-of-file
filenoReturns file descriptor for a filehandle
getcReturns next character from input file
printPrints a string or comma-separated list of strings
printfPrints a formatted string
readReads data from a filehandle
statReturns an array of status information for a file
sysreadReads data from a filehandle with system call read(2)
syswriteWrites data to a filehandle with system call write(2)
truncateTruncates a file to a specified length

Finally, the following methods act on the equivalent Perl variables. See Chapter 4 for more information.


If nonzero, forces a flush now and after each write or print (default 0)

format_page_numberCurrent page number
format_lines_per_pageCurrent page length (default 60)
format_lines_leftNumber of lines left on page
format_nameName of current report format
format_top_nameName of current top-of-page format

Current set of linebreak chars for a format


Formfeed char used by formats (default \f)

format_writeWrapper for write function
input_record_separatorInput record separator (default newline)

Current input line number for last filehandle accessed


Output field separator for print


Output record separator for print

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