RFIO_OPEN(3) Rfio Library Functions RFIO_OPEN(3)
NAME
rfio_open - opens a file
SYNOPSIS
#include <sys/types.h>
#include "rfio_api.h"
int rfio_open (const char *path, int flags, int mode);
Under Linux, for large files:
#define _LARGEFILE64_SOURCE
#include <sys/types.h>
#include "rfio_api.h"
int rfio_open64 (const char *path, int flags, int mode);
For large files, under other systems:
#include <sys/types.h>
#include "rfio_api.h"
int rfio_open64 (const char *path, int flags, int mode);
DESCRIPTION
rfio_open opens the file whose name is the string pointed to by path, a character string containing the filename specification, and asso-
ciates a FILE stream with it.
flags are formed by ORing the following values:
O_RDONLY Open for reading only
O_WRONLY Open for writing only
O_RDWR Open for reading and writing
O_NDELAY Do not block on open
O_APPEND Append on each write
O_CREAT Create file if it does not exist
O_TRUNC Truncate size to 0
O_EXCL Error if create and file exists
O_LARGEFILE When size can be superior to 2GB-1.
See NOTES
mode specifies the permission bits to be set if the file is created.
Opening a file with O_APPEND set causes each write on the file to be appended to the end. If O_TRUNC is specified and the file exists, the
file is truncated to zero length. If O_EXCL is set with O_CREAT, then if the file already exists, the open returns an error. This can be
used to implement a simple exclusive access locking mechanism. If O_EXCL is set and the last component of the pathname is a symbolic link,
the open will succeed even if the symbolic link points to an existing name. If the O_NDELAY flag is specified and the open call would
result in the process being blocked for some reason (for example waiting for a carrier on a dial-up line), the open returns immediately.
The first time the process attempts to perform IO on the open file, it will block (not currently implemented). On systems that support the
Large Files, O_LARGEFILE in rfio_open allows files whose sizes cannot be represented in 31 bits to be opened.
RETURN VALUE
If successful, returns a non-negative integer which may be used to refer to the file on subsequent rfio_write, rfio_read and rfio_close
calls. On failure, rfio_open returns -1 and the error code is stored in serrno.
ERRORS
ENOENT The named file/directory does not exist or is a null pathname.
EACCES Search permission is denied on a component of the path prefix.
EBUSY Device or resource busy. Happens if you try to open in write mode a LCG file that is in an active migration stream.
EFAULT path is a NULL pointer.
ENOTDIR A component of path prefix is not a directory.
ENAMETOOLONG The length of path exceeds CA_MAXPATHLEN or the length of a path component exceeds CA_MAXNAMELEN.
SENOSHOST Host unknown.
SENOSSERV Service unknown.
SECOMERR Communication error.
SEE ALSO
Castor_limits(4),rfio_write(3),rfio_read(3),rfio_close(3)
NOTES
On Irix, Tru64 and IA64 the 64 bit mode is the default one, open and open64 are identical. The flag O_LARGEFILE is accepted on Irix and
IA64 (where it has no effect) but not on Tru64. On all other platforms, rfio_open with O_LARGEFILE is equivalent to a call to rfio_open64.
AUTHOR
LCG Grid Deployment Team
LCG
$Date: 2005/03/31 13:13:03 $ RFIO_OPEN(3)