dpns_readdirg(3) - Linux man page

Name

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

Synopsis

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

struct dpns_direnstatg *dpns_readdir (dpns_DIR *dirp)

Description

dpns_readdir reads the DPNS directory opened by dpns_opendir in the name server. This routine returns a pointer to a structure containing the current directory entry including the GUID associated.

struct dpns_direnstatg {
    u_signed64    fileid;
    char        guid[CA_MAXGUIDLEN+1];
    mode_t        filemode;
    int        nlink;        /* number of files in a directory */
    uid_t        uid;
    gid_t        gid;
    u_signed64    filesize;
    time_t        atime;        /* last access to file */
    time_t        mtime;        /* last file modification */
    time_t        ctime;        /* last metadata modification */
    short        fileclass;    /* not used */
    char        status;        /* ' ' --> online, 'm' --> migrated */
    char        csumtype[3];    /* "CS", "AD" or "MD" */
    char        csumvalue[33];
    unsigned short    d_reclen;    /* length of this entry */
    char        d_name[1];    /* basename in variable length */
};

dpns_readdir 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.

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_readdir 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_readdir, then check serrno and if it is non-zero, assume an error has occurred.

Errors

EBADF: File descriptor in DIR structure is invalid.
EFAULT: dirp is a NULL pointer.
SECOMERR: Communication error.
ENSNACT: Name server is not running or is being shutdown.

Author

LCG Grid Deployment Team