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 associates
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 path
- name.
- 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