V1/man/man2/write.2

        11/3/71                                               SYS WRITE (II)


NAME              write ---- write, on file

SYNOPSIS          (file descriptor in r0)
                  sys      write; buffer; nchars        / write = 4.
                  (number written in r0)

DESCRIPTION       A file descriptor is a word returned from a successful open or creat
                  call.

                  buffer is the address of nchars contiguous bytes which are written on
                  the output file. The number of characters actually written is
                  returned in r0. It should be regarded as an error if this is not the
                  same as requested.

                  For disk and tape files, writes which are multiples of 512 characters
                  long and begin on a 512--byte boundary are more efficient than any
                  others.

FILES

SEE ALSO          sys creat, sys open

DIAGNOSTICS       The error bit (c--bit) is set on an error: bad descriptor, buffer
                  address, or count. physical I/o errors;

BUGS

OWNER             ken, dmr