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DPNS_READDIRG(3) DPNS Library Functions DPNS_READDIRG(3)

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.

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

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

SEE ALSO

dpns_closedir(3), dpns_opendir(3), dpns_rewinddir(3)

AUTHOR

LCG Grid Deployment Team

$Date$ DPNS