RFIOSETOPT(3)						      Rfio Library Functions						     RFIOSETOPT(3)

NAME

       rfiosetopt - set RFIO options

SYNOPSIS

       #include <sys/types.h>
       #include "rfio_api.h"

       int rfiosetopt (int opt, int *pval, int len)

       int rfio_setbufsize (int s, int bufsize)

DESCRIPTION

       rfiosetopt sets the RFIO option opt to the content of the memory cell pointed by pval.

       rfio_setbufsize sets the size of the readahead buffer to be used on a particular socket connection.

       opt can have on of the following values:

	      RFIO_READOPT
		     The value pointed by pval can be 0, RFIO_READBUF, RFIO_READAHEAD or RFIO_STREAM (V3).

		     If set to zero, a normal read will be used (one request to the server per read).

		     If  set to RFIO_READBUF, an internal buffer is allocated in the client API, each call to the server fills this buffer and the
		     user buffer is filled from the internal buffer. There is one server call per buffer fill.

		     If set to RFIO_READAHEAD, an initial call is sent to the server which pushes data to the client buffer until end of  file	is
		     reached  or  an  error  occurs  or  a  new  request comes from the client.  There is no intermediate buffer unless RFIO_READ-
		     BUF|RFIO_READAHEAD is specified.

		     If RFIO_STREAM is set, the V3 protocol is enabled.  This uses 2 socket connections between the client and the server and  the
		     server itself is multi-threaded allowing overlap of disk and network operations.  The data is pushed on the data socket until
		     end of file is reached or an error occurs. The transfer can be interrupted by sending a packet on the control socket.
		     Default is RFIO_READBUF.

		     The default internal buffer size is 128kB, but the buffer size can be set with an entry RFIO IOBUFSIZE in shift.conf or  thru
		     the environment variable RFIO_IOBUFSIZE.

	      RFIO_NETOPT
		     The  value  pointed  by pval can be RFIO_NONET or RFIO_NET.  If set to RFIO_NONET, the NET entries in shift.conf are ignored.
		     Default is RFIO_NET.

	      RFIO_NETRETRYOPT
		     The value pointed by pval can be RFIO_RETRYIT or RFIO_NOTIME2RETRY.

		     If set to RFIO_RETRYIT, there will be retries on failing connect.	The number of retries is given by the environment variable
		     RFIO_CONRETRY or the RFIO CONRETRY entry in shift.conf.  The retry interval (in seconds) is given by the environment variable
		     RFIO_CONRETRYINT or the RFIO CONRETRYINT entry.

		     If set to RFIO_NOTIME2RETRY, there will be no retry on failing connect.
		     Default is RFIO_RETRYIT.

	      RFIO_CONNECTOPT
		     The value pointed by pval can be RFIO_NOLOCAL or RFIO_FORCELOCAL.	If set to RFIO_FORCELOCAL, no parsing is done on pathname.
		     The file is assumed to be local.  Default is RFIO_NOLOCAL.

       The len argument is ignored.

       s is the file descriptor of the receiving socket.

       bufsize is the size of the readahead buffer to be used.

RETURN VALUE

       rfiosetopt returns 0 if the operation was successful or -1 if the operation failed.  In the latter case, serrno is set appropriately.

ERRORS

       ENOMEM	    buffer could not be allocated.

       EINVAL	    opt is not a valid option, bufsize is negative or the user tries to change the buffer size after the actual I/O has started.

SEE ALSO

       rfio_open(3), rfioreadopt(3)

AUTHOR

       LCG Grid Deployment Team

LCG
					       $Date: 2010-02-15 10:01:40 +0100 (Mon, 15 Feb 2010) $				     RFIOSETOPT(3)