dpns_readdirxp(3) - Linux man page

Name

dpns_readdirxp - read DPNS directory opened by dpns_opendir in the name server

Synopsis

#include <sys/types.h>
#include "dpns_api.h"

struct dpns_direnrep *dpns_readdirxp (dpns_DIR *dirp, char *pattern, char *se)

Description

dpns_readdirxp reads the DPNS directory opened by dpns_opendir in the name server. It does restricted pattern matching on basename. This routine returns a pointer to a structure containing the current directory entry (basename, guid and filesize) and the replica information.

struct dpns_rep_info {
    u_signed64    fileid;
    char        status;
    char        *host;
    char        *sfn;
};
struct dpns_direnrep {
    u_signed64    fileid;
    char        guid[CA_MAXGUIDLEN+1];
    mode_t        filemode;
    u_signed64    filesize;
    int        nbreplicas;
    struct dpns_rep_info *rep;    /* array of replica info structures */
    unsigned short    d_reclen;    /* length of this entry */
    char        d_name[1];    /* basename in variable length */
};

dpns_readdirxp caches a variable number of such entries, depending on the filename size, to minimize the number of requests to the name server.

dirp: specifies the pointer value returned by dpns_opendir.
pattern: allows to restrict the listing to entries having the basename starting with this pattern.
se: allows to restrict the replica entries to a given SE.

Return Value

This routine returns a pointer to a structure containing the current directory entry if the operation was successful or NULL if the end of the directory was reached or if the operation failed. When the end of the directory is encountered, serrno is not changed. If the operation failed, serrno is set appropriately.

As dpns_readdirxp returns a null pointer both at the end of the directory and on error, an application wishing to check for error situations should set serrno to 0, then call dpns_readdirxp, then check serrno and if it is non-zero, assume an error has occurred.

Errors

EBADF: File descriptor in DIR structure is invalid.
ENOMEM: Memory could not be allocated for unmarshalling the reply.
EFAULT: dirp is a NULL pointer.
EINVAL: The length of pattern exceeds CA_MAXNAMELEN or the length of se exceeds CA_MAXHOSTNAMELEN.
SECOMERR: Communication error.
ENSNACT: Name server is not running or is being shutdown.

Author

LCG Grid Deployment Team