|Perl Language Reference Manual|
by Larry Wall and others
Paperback (6"x9"), 724 pages
RRP £29.95 ($39.95)
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Attempts to write LENGTH bytes of data from variable SCALAR to the
specified FILEHANDLE, using write(2). If LENGTH is
not specified, writes whole SCALAR. It bypasses buffered IO, so
mixing this with reads (other than
eof may cause confusion because the perlio and
stdio layers usually buffers data. Returns the number of bytes
actually written, or
undef if there was an error (in this case the
$! is also set). If the LENGTH is greater than the
data available in the SCALAR after the OFFSET, only as much data as is
available will be written.
An OFFSET may be specified to write the data from some part of the string other than the beginning. A negative OFFSET specifies writing that many characters counting backwards from the end of the string. If SCALAR is of length zero, you can only use an OFFSET of 0.
Warning: If the filehandle is marked
:utf8, Unicode characters
encoded in UTF-8 are written instead of bytes, and the LENGTH, OFFSET, and
return value of syswrite() are in (UTF-8 encoded Unicode) characters.
:encoding(...) layer implicitly introduces the
See , , and the
open pragma, "Perl pragma to set default PerlIO layers for input and output" (open) in the Perl Library Reference Manual (Volume 1).
|ISBN 9781906966027||Perl Language Reference Manual||See the print edition|