READ - read from a file.
(Compatible with UNIX System V C)
Usage:
#include <fildes.h>
ret = read( fd, buf, N );
Where:
- int fd;
- is the file descriptor of a file open for reading (as
returned by "open" or "creat").
- char *buf;
- points to an area of memory into which the data should be
read.
- unsigned N;
- is the maximum number of bytes to read.
- int ret;
- is the number of bytes actually read. If the operation
failed, a -1 is returned and the library variable ERRNO
is set to indicate the error (see "expl c lib errno").
Description:
"read" reads in data from the position indicated by
the current file pointer associated with the given file
descriptor.
Possible Errors:
- errno=EBADF
- "fd" was invalid.
- errno=EINVAL
- N was less than zero.
- errno=EIO
- an I/O error occurred.
Notes:
This function exists solely for compatibility with existing
software. New programs should use the "fread"
function instead.
You must #include <fildes.h>; otherwise, the reference
to "read" will be resolved to a different, incompatible
function.
See Also:
expl c lib open
expl c lib write
expl c include fildes
Copyright © 1996, Thinkage Ltd.