.TH mtcp_setsockopt 3 2017-02-02 "Linux" "mOS Library Functions Manual"
.SH NAME
mtcp_setsockopt \- set options on mTCP/mOS sockets
.SH SYNOPSIS
.B #include <mtcp_api.h>
.sp

.BI "int mtcp_setsockopt(mctx_t " mctx ", int " sockid ", int " level ", int " optname ", const void *" optval ", socklen_t " optlen );

.SH DESCRIPTION
.BR mtcp_setsockopt ()
manipulate options for the socket referred to by the
.I "sockid"
descriptor. These options may exist at multiple protocol
levels. When manipulating socket options, the level at
which the options resides and the name of the option
must be specified. A user can use
.BR "SOL_MONSOCKET"
.I "level"
to adjust options for monitoring sockets.

The arguments
.I "optval"
and
.I "optlen"
are used to set options values for mtcp_setsockopt().

SOL_MONSOCKET socket
.I level
can be used by
.BR mtcp_setsockopt()
to set a number of attributes pertaining to the socket.

.TP 25
.IP "MOS_CLIBUF"
Dynamically adjust the size of the TCP receive ring buffer
of the emulated client stack. The
.I optval
contains the size of the buffer that needs to be set as int, while
.I optlen
is equal to sizeof(int).

.IP "MOS_SVRBUF"
Dynamically adjust the size of the TCP receive ring buffer
of the emulated client stack. The
.I optval
contains the size of the buffer that needs to be set as int, while
.I optlen
is equal to sizeof(int).

.\""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.SH RETURN VALUE
Returns 0 on success; -1 on failure. In case
of failure,
.I "errno"
is set appropriately.
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.SH ERRORS
.TP 10
.B "EACCES"
.I "mctx"
is not valid.

.TP 10
.B "EBADF"
.I "sockid"
is not a valid socket descriptor.

.TP 10
.B "ENOTSOCK"
The socket referred to by
.I "sockid"
is not valid.

.TP 10
.B "ENOSYS"
Either the
.I "level"
or the
.I "optname"
is not implemented.

.TP 10
.B "EPERM"
Permission to access a socket option is denied.

.TP 10
.B 
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.\""""".SH CONFORMING TO
.\"""""POSIX.1-2001.
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.SH AUTHORS
mOS development team <mtcp-user@list.ndsl.kaist.edu>
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.SH SEE ALSO
.BR mtcp_socket (), 
.BR mtcp_getsockopt ()
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.SH COLOPHON
This page is part of mOS release 0.3
.I "docs"
section. A description of the project, and information
about reporting bugs, can be found at
\%http://mos.kaist.edu/.
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""