QlgReaddir_r()--Read Directory Entry (using NLS-enabled path name)

 #include <sys/types.h>
 #include <dirent.h>

 int QlgReaddir_r(DIR *dirp, struct dirent_lg *entry,  
                  struct dirent_lg **result);  

The QlgReaddir_r() function, like the readdir_r() function, initializes a structure that is referenced by entry to represent the next directory entry in the directory stream that is associated with dirp. The difference is that the QlgReaddir_r() entry and result parameters point to dirent_lg structures, while the readdir_r() entry and result parameters point to dirent structures.

The QlgReaddir_r functions stores a pointer to the entry structure at the location referenced by result.

The QlgReaddir_r() function converts the directory entry name into the CCSID (coded character set identifier) of the job at the time of the call to opendir(), or to the CCSID specified on the call to QlgOpendir(). If the directory entry name cannot be represented in that CCSID, then that directory entry will not be returned by QlgReaddir_r() and no error indication will occur.

QlgOpendir() allows the CCSID to be specified in the Qlg_Path_Name_T structure. See QlgOpendir()--Open Directory (using NLS-enabled path name) for more information.

Limited information about the dirp parameter, the entry parameter, and the result parameter is provided here. For more information about these parameters and for a discussion of authorities required, return values, and related information, see readdir_r()--Read Directory Entry.

Parameters

dirp

(Input) A pointer to a DIR that refers to the open directory stream to be read. This pointer is returned by QlgOpendir() or opendir().

entry

(Output) A pointer to a dirent_lg structure in which the directory entry is to be placed.

result

(Output) A pointer to a pointer to a dirent_lg structure. Upon successfully reading a directory entry, this dirent_lg pointer is set to the same value as entry. Upon reaching the end of the directory stream, this pointer is set to NULL.

A dirent_lg structure has the following contents:

char	d_reserved1[16]	Reserved.
unsigned int	d_fileno_gen_id	The generation ID associated with the file ID.
ino_t	d_fileno	The file ID of the file. This number uniquely identifies the object within a file system.
unsigned int	d_reclen	The length of the directory entry in bytes.
int	d_reserved3	Reserved.
char	d_reserved4[6]	Reserved.
char	d_reserved5[2]	Reserved.
Qlg_Path_Name_T	d_lg_name	A Qlg_Path_Name_T structure that gives the name of a file in the directory. The path name is not null-terminated within the structure. The structure also provides National Language Support information, which includes ccsid, country_id, and language_id. This structure has a maximum length of {_QP0L_DIR_NAME_LG} bytes. For more information about the Qlg_Path_Name_T structure, see Path name format.

Related Information

• The <sys/types.h> file (see Header Files for UNIX^®-Type Functions)
• The <dirent.h> file (see Header Files for UNIX-Type Functions)
• readdir_r()--Read Directory Entry
• readdir_r_ts64()--Read Directory Entry
• readdir()--Read Directory Entry
• QlgReaddir()--Read Directory Entry (using NLS-enabled path name)
• opendir()--Open Directory
• QlgOpendir()--Open Directory (using NLS-enabled path name)
• rewinddir()--Reset Directory Stream to Beginning
• closedir()--Close Directory
• pathconf()--Get Configurable Path Name Variables
• QlgPathconf()--Get Configurable Path Name Variables (using NLS-enabled path name)

Example

The following example reads the contents of a root directory.

Note: By using the code examples, you agree to the terms of the Code license and disclaimer information.

#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <stdio.h>

main() {
  int return_code;
  DIR *dir;
  struct dirent_lg entry;
  struct dirent_lg *result;

  typedef struct my_dirent_lg
  {
    struct dirent_lg *entry;
    char          d_lg_name[1];
  };
  struct my_dirent_lg lg_struct;

#define mypath "/"
  const char US_const[3]= "US";
  const char Language_const[4]="ENU";
  typedef struct pnstruct
  {
    Qlg_Path_Name_T qlg_struct;
    char pn[100];  /* This array size must be >=   */
                         /* the length of the path name or this */
                         /* must be a pointer to the path name. */
  };
  struct pnstruct path;

   /***************************************************************/
   /*   Initialize Qlg_Path_Name_T parameters                     */
   /***************************************************************/
  memset((void*)&path, 0x00, sizeof(struct pnstruct));
  path.qlg_struct.CCSID = 37;
  memcpy(path.qlg_struct.Country_ID,US_const,2);
  memcpy(path.qlg_struct.Language_ID,Language_const,3);
  path.qlg_struct.Path_Type = QLG_CHAR_SINGLE;
  path.qlg_struct.Path_Length = sizeof(mypath)-1;
  path.qlg_struct.Path_Name_Delimiter[0] = '/';
  memcpy(path.pn,mypath,sizeof(mypath)-1);

  if ((dir = QlgOpendir((Qlg_Path_Name_T *)&path)) == NULL)
    perror("QlgOpendir() error");
  else {
    puts("contents of root:");
    for (return_code = QlgReaddir_r(dir, &entry, &result);
         result != NULL && return_code == 0;
         return_code = QlgReaddir_r(dir, &entry, &result))
      printf("  %s\n", entry.d_lg_name);
    if (return_code != 0)
      perror("QlgReaddir_r() error");
    closedir(dir);
  }
}

Output:

contents of root:
  .
  ..
  QSYS.LIB
  QDLS
  QOpenSys
  QOPT
  home

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