.TH BUS_CLOSE 1 BUS-%VERSION%
.SH NAME
bus_read - Listen for new messages a bus
.SH SYNOPSIS
#include <bus.h>

int bus_read(const bus_t *bus, int (*callback)(const char *message, void *user_data), void *user_data);
.SH DESCRIPTION
The \fIbus_read\fP function shall continuously wait for new message to be sent on the bus whose information is stored in \fIbus\fP. Once a message is received, the \fIcallback\fP function shall be invoked. \fImessage\fP should be the recieved message, and \fIuser_data\fP for \fIcallback\fP should be \fIuser_data\fP from \fIbus_read\fP.

After \fIcallback\fP returns, \fImessage\fP may be override. Therefore \fIcallback\fP should copy \fImessage\fP and start a new thread that uses the copy of \fImessage\fP. \fIcallback\fP shall return -1 on failure, 0 if \fIbus_read\fP should stop listening or 1 if \fIbus_read\fP should continue listening.
.SH RETURN VALUES
Upon successful completion, the function shall return 0. Otherwise the function shall return -1 and set \fIerrno\fP to indicate the error.
.SH ERRORS
The \fIbus_read\fP() function may fail and set \fIerrno\fP to any of the errors specified for the rutine semop(3).
.SH SEE ALSO
bus-create(1), bus(5), libbus(7), bus_open(3), bus_write(3)
.SH AUTHORS
See the LICENSE file for the authors.
.SH LICENSE
See the LICENSE file for the terms of redistribution.
.SH BUGS
Please report them.