sysreadFILEHANDLE
,SCALAR
,LENGTH
,OFFSET
sysreadFILEHANDLE
,SCALAR
,LENGTH
This function attempts to read
LENGTH
bytes of data into variable
SCALAR
from the specified
FILEHANDLE
using
read
(2). The function returns the number of bytes actually read, or 0 at EOF. It returns the undefined value on error.
SCALAR
will be grown or shrunk to the length actually read. The
OFFSET
, if specified, says where in the string to start putting the bytes, so that you can read into the middle of a string that's being used as a buffer. For an example, see
syswrite
. You should be prepared to handle the problems (like interrupted system calls) that standard I/O normally handles for you. Also, do not mix calls to
read
and
sysread
on the same filehandle unless you are into heavy wizardry (and/or pain).