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_READBUF|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