RFIO_SYMLINK
Section: Rfio Library Functions (3)
Updated: $Date: 2005/03/31 13:13:03 $
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NAME
rfio_symlink - create a symbolic link to a file
SYNOPSIS
#include <sys/types.h>
#include "rfio_api.h"
int rfio_symlink (const char *oldpath, const char *newpath);
int rfio_msymlink (const char *oldpath, const char *newpath);
int rfio_msymlink_reset ();
int rfio_symend ();
DESCRIPTION
rfio_symlink
creates a symbolic link
newpath
which contains the string
oldpath.
newpath
may point to a non existing file.
If
newpath
exists already, it will not be overwritten.
Write permission is required on
newpath
parent.
rfio_msymlink
is identical to
rfio_symlink
but keeps the connection open to the server unless there are more than MAXMCON
connections already opened. This is useful when issuing a series of symlink calls.
The last
rfio_msymlink
call should be followed by a call to
rfio_symend.
rfio_msymlink_reset
is to be used when your program is forking. In such a case the permanent connections opened with
rfio_msymlink
become shared between the parent and the child. Use
rfio_msymlink_reset
to perform the necessary reset and close of the socket file descriptor in the parent or the child in order to be sure that only of them will receice an answer from the RFIO daemon.
See NOTES section below.
RETURN VALUE
This routine returns 0 if the operation was successful or -1 if the operation
failed. In the latter case,
serrno
is set appropriately.
NOTES
Multiple connections using rfio_msymlink are thread-safe but not process-wide, therefore a forked child can share file descriptors opened with rfio_msymlink by its parent. Use
rfio_msymlink_reset
in such case.
Multiple connections behaviour is undefined if you work in a multi-threaded environment and with threads not created using the LCG's Cthread interface.
ERRORS
- ENOENT
-
A component of
newpath
prefix does not exist or
oldpath
is a null pathname.
- ENOMEM
-
Insufficient memory.
- EACCES
-
Search permission is denied on a component of the
newpath
prefix or write permission on the
newpath
parent directory is denied.
- EFAULT
-
oldpath
or
newpath
is a NULL pointer.
- EEXIST
-
newpath
already exists.
- ENOTDIR
-
A component of the
newpath
prefix is not a directory.
- ENAMETOOLONG
-
The length of
oldpath
or
newpath
exceeds
CA_MAXPATHLEN
or the length of a path component exceeds
CA_MAXNAMELEN.
- SENOSHOST
-
Host unknown.
- SENOSSERV
-
Service unknown.
- SECOMERR
-
Communication error.
- SEOPNOTSUP
-
Not supported on Windows.
SEE ALSO
Castor_limits(4),
rfio_readlink(3),
rfio_unlink(3),
Cthread(3)
AUTHOR
LCG Grid Deployment Team