READ(3spp) RISC/os Reference Manual READ(3spp)
NAME
read - read input
SYNOPSIS
cc = read(fd, buf, nbytes)
int cc, fd;
char *buf;
int nbytes;
DESCRIPTION
Read attempts to read nbytes of data from the object refer-
enced by the file descriptor fd into the buffer pointed to
by buf.
On objects capable of seeking, the read starts at a position
given by the pointer associated with fd (see lseek(2)).
Upon return from read, the pointer is incremented by the
number of bytes actually read.
Objects that are not capable of seeking always read from the
current position. The value of the pointer associated with
such an object is undefined.
Upon successful completion, read returns the number of bytes
actually read and placed in the buffer. The system guaran-
tees to read the number of bytes requested if the file
descriptor references a normal file that has that many bytes
left before the end-of-file, but in no other case.
If the returned value is 0, then end-of-file has been
reached.
RETURN VALUE
If successful, the number of bytes actually read is
returned. Otherwise, a -1 is returned and the global vari-
able errno is set to indicate the error.
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