stat64()--Get File Information (Large File Enabled)


  Syntax
 #include <sys/stat.h>

 int stat64(const char *path, struct stat64 *buf);  
  Service Program Name: QP0LLIB1

  Default Public Authority: *USE

  Threadsafe: Conditional; see Usage Notes.

The stat64() function gets status information about a specified file and places it in the area of memory pointed to by the buf argument.

If the named file is a symbolic link, stat64() resolves the symbolic link. It also returns information about the resulting file.

stat64() is enabled for large files. It is capable of operating on files larger than 2GB minus 1 byte and returning correct sizes.

For additional information about authorities required, error conditions, and examples, see stat()--Get File Information.


Parameters

path
(Input) A pointer to the null-terminated path name of the file from which information is required.

This parameter is assumed to be represented in the CCSID (coded character set identifier) currently in effect for the job. If the CCSID of the job is 65535, this parameter is assumed to be represented in the default CCSID of the job.

See QlgStat64()--Get File Information (large file enabled and using NLS-enabled path name) for a description and an example of supplying the path in any CCSID.


buf
(Output) A pointer to the area to which the information should be written.

The information is returned in the following stat64 structure, as defined in the <sys/stat.h> header file:

mode_t st_mode A bit string indicating the permissions and privileges of the file. Symbols are defined in the <sys/stat.h> header file to refer to bits in a mode_t value; these symbols are listed in chmod()--Change File Authorizations.

ino_t st_ino The file ID for the object. This number uniquely identifies the object within a file system. When st_ino and st_dev are used together, they uniquely identify the object on the system.

uid_t st_uid The numeric user ID (uid) of the owner of the file.

gid_t st_gid The numeric group ID (GID) for the file.

off64_t st_size Defined as follows for each file type:
Regular File
The number of data bytes in the file.
Directory
The number of bytes allocated to the directory.
Symbolic Link
The number of bytes in the path name stored in the symbolic link.
Local Socket
Always zero.
Operating System Native Object
This value is dependent on the object type.
time_t st_atime The most recent time the file was accessed.

time_t st_mtime The most recent time the contents of the file were changed.

time_t st_ctime The most recent time the status of the file was changed.

dev_t st_dev The file system ID to which the object belongs. This number uniquely identifies the file system to which the object belongs. When st_ino and st_dev are used together, they uniquely identify the object on the system. This field will be 4,294,967,295 if the value could not fit in the specified dev_t field. The complete value will be in the st_dev64 field.

size_t st_blksize The block size of the file in bytes. This number is the number of bytes in a block of disk unit storage.

nlink_t st_nlink The number of links to the file. This field will be 65,535 if the value could not fit in the specified nlink_t field. The complete value will be in the st_nlink32 field.

unsigned short st_codepage The code page derived from the CCSID used for the data in the file or the extended attributes of the directory. If the returned value of this field is 0, a code page could not be derived.

unsigned long long st_allocsize The number of bytes allocated to the file. The allocated size varies by object type and file system. For example, the allocated size includes the object data size as shown in st_size as well as any logically sized extents to accomodate anticipated future requirements for the object data. It may or may not include additional bytes for attribute information.

unsigned int st_ino_gen_id The generation ID associated with the file ID.

qp0l_objtype_t st_objtype The object type; for example, *STMF or *DIR. Refer to CL programming topic for a list of the object types.

char st_reserved2[5] Reserved.

dev-t st_rdev The device ID of the object if the object is a character special file or block special file. This number uniquely identifies the file device. This field will be 4,294,967,295 if the value could not fit in the specified dev_t field. The complete value will be in the st_rdev64 field.

dev64_t st_rdev64 The device ID of the object in 64 bit format. See st_rdev for more information.

dev64_t st_dev64 The file system ID to which the object belongs in 64 bit format. See st_dev for more information.

nlink32_t st_nlink32 The number of links to the file.

unsigned int st_vfs The unique mount ID of the file system on which the object is located. Information about each mounted file system can be obtained by using the QP0L_RETRIEVE_MOUNTED_FILE_SYSTEMS option of the Perform File System Operation (QP0LFLOP) API.
Unlike st_dev and st_dev64, st_vfs identifies a particular instance of a file system. For any single file system, st_dev and st_dev64 will remain the same across multiple mounts. In contrast, st_vfs is incremented whenever a file system is mounted and is different for each mount of a file system. Therefore, the value of st_vfs may change due to any system processing which unmounts and mounts file systems, such as IPL and Reclaim Storage (RCLSTG).
char st_reserved1[22] Reserved.

unsigned short st_ccsid The CCSID used for the data in the file or the extended attributes of the directory.

Values of time_t are given in terms of seconds since a fixed point in time called the Epoch.

You can examine properties of a mode_t value from the st_mode field using a collection of macros defined in the <sys/stat.h> header file. If mode is a mode_t value, then:

S_ISBLK(mode)
Is nonzero for block special files
S_ISCHR(mode)
Is nonzero for character special files
S_ISDIR(mode)
Is nonzero for directories
S_ISFIFO(mode)
Is nonzero for pipes and FIFO special files
S_ISREG(mode)
Is nonzero for regular files
S_ISLNK(mode)
Is nonzero for symbolic links
S_ISSOCK(mode)
Is nonzero for local sockets
S_ISNATIVE(mode)
Is nonzero for operating system native objects

Usage Notes

  1. When you develop in C-based languages, the prototypes for the 64-bit APIs are normally hidden. To use either the stat64() API or the QlgStat64() API and the struct stat64 data type, you must compile the source with _LARGE_FILE_API defined.
  2. All of the usage notes for stat() also apply to stat64() and to QlgStat64(). See Usage Notes in the stat() API.

API introduced: V4R4

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