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 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