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