WRITE(II) 8/5/73 WRITE(II)
NAME
write - write on a file
SYNOPSIS
(write = 4.)
(file descriptor in r0)
sys write; buffer; nbytes
write(fildes, buffer, nbytes)
char *buffer;
DESCRIPTION
A file descriptor is a word returned from a successful open,
creat, dup, or pipe call.
Buffer is the address of nbytes contiguous bytes which are
written on the output file. The number of characters actu-
ally written is returned (in r0). It should be regarded as
an error if this is not the same as requested.
Writes which are multiples of 512 characters long and begin
on a 512-byte boundary in the file are more efficient than
any others.
SEE ALSO
creat(II), open(II), pipe(II)
DIAGNOSTICS
The error bit (c-bit) is set on an error: bad descriptor,
buffer address, or count; physical I/O errors. From C, a
returned value of -1 indicates an error.
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