Xinu7/man/man2/send.2

.TH SEND 2
.SH NAME
send \- send a (one-word) message to a process
.SH SYNOPSIS
.nf
.B int send(pid, msg)
.B int pid;
.B int msg;
.fi
.SH DESCRIPTION
.I Send
sends the one-word message
.I msg
to the process with id
.I pid.
A process may have at most one outstanding message that has
not been received.
.PP
.I Send
returns SYSERR if
.I pid
is invalid or if the process already has a message waiting
that has not been received.
Otherwise, it sends the message and returns OK.
.SH SEE ALSO
receive(2), sendf(2), preceive(2), psend(2)