- syswrite
FILEHANDLE,SCALAR,LENGTH,OFFSET
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- syswrite FILEHANDLE,SCALAR,LENGTH
-
- syswrite FILEHANDLE,SCALAR
-
Attempts to write LENGTH characters of data from variable SCALAR to the specified
FILEHANDLE, using the system call write(2). If LENGTH is not specified, writes whole
SCALAR. It bypasses buffered IO, so mixing this with reads (other than sysread()),
print, write, seek, tell, or eof
may cause confusion because stdio usually buffers data. Returns the number of characters
actually written, or undef if there was an error. If the LENGTH is greater
than the available data 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. In the case the SCALAR is empty you can use OFFSET but only
zero offset.
Note the characters: depending on the status of the filehandle, either (8-bit)
bytes or characters are written. By default all filehandles operate on bytes, but for
example if the filehandle has been opened with the :utf8 I/O layer (see /open, and the open pragma,
open), the I/O will operate
on characters, not bytes.
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