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SunOS man pages : fstat (2)

System Calls                                              stat(2)

NAME

stat, lstat, fstat - get file status

SYNOPSIS

#include <sys/types.h> #include <sys/stat.h> int stat(const char *path, struct stat *buf); int lstat(const char *path, struct stat *buf); int fstat(int fildes, struct stat *buf);

DESCRIPTION

The stat() function obtains information about the file pointed to by path. Read, write, or execute permission of the named file is not required, but all directories listed in the path name leading to the file must be searchable. The lstat() function obtains file attributes similar to stat(), except when the named file is a symbolic link; in that case lstat() returns information about the link, while stat() returns information about the file the link refer- ences. The fstat() function obtains information about an open file known by the file descriptor fildes, obtained from a suc- cessful open(2), creat(2), dup(2), fcntl(2), or pipe(2) function. The buf argument is a pointer to a stat structure into which information is placed concerning the file. A stat structure includes the following members: mode_t st_mode; /* File mode (see mknod(2)) */ ino_t st_ino; /* Inode number */ dev_t st_dev; /* ID of device containing */ /* a directory entry for this file */ dev_t st_rdev; /* ID of device */ /* This entry is defined only for */ /* char special or block special files */ nlink_t st_nlink; /* Number of links */ uid_t st_uid; /* User ID of the file's owner */ gid_t st_gid; /* Group ID of the file's group */ off_t st_size; /* File size in bytes */ time_t st_atime; /* Time of last access */ time_t st_mtime; /* Time of last data modification */ time_t st_ctime; /* Time of last file status change */ /* Times measured in seconds since */ /* 00:00:00 UTC, Jan. 1, 1970 */ long st_blksize; /* Preferred I/O block size */ blkcnt_t st_blocks; /* Number of 512 byte blocks allocated*/ SunOS 5.8 Last change: 28 Jan 1998 1 System Calls stat(2) Descriptions of structure members are as follows: st_mode The mode of the file as described in mknod(2). In addition to the modes described in mknod(), the mode of a file may also be S_IFLNK if the file is a sym- bolic link. S_IFLNK may only be returned by lstat(). st_ino This field uniquely identifies the file in a given file system. The pair st_ino and st_dev uniquely identifies regular files. st_dev This field uniquely identifies the file system that contains the file. Its value may be used as input to the ustat() function to determine more information about this file system. No other meaning is associated with this value. st_rdev This field should be used only by administrative com- mands. It is valid only for block special or character special files and only has meaning on the system where the file was configured. st_nlink This field should be used only by administrative com- mands. st_uid The user ID of the file's owner. st_gid The group ID of the file's group. st_size For regular files, this is the address of the end of the file. For block special or character special, this is not defined. See also pipe(2). st_atime Time when file data was last accessed. Changed by the following functions: creat(), mknod(), pipe(), utime(2), and read(2). st_mtime Time when data was last modified. Changed by the fol- lowing functions: creat(), mknod(), pipe(), utime(), and write(2). st_ctime SunOS 5.8 Last change: 28 Jan 1998 2 System Calls stat(2) Time when file status was last changed. Changed by the following functions: chmod(), chown(), creat(), link(2), mknod(), pipe(), unlink(2), utime(), and write(). st_blksize A hint as to the "best" unit size for I/O operations. This field is not defined for block special or charac- ter special files. st_blocks The total number of physical blocks of size 512 bytes actually allocated on disk. This field is not defined for block special or character special files.

RETURN VALUES

Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

The stat(), fstat(), and lstat() functions will fail if: EOVERFLOW The file size in bytes or the number of blocks allo- cated to the file or the file serial number cannot be represented correctly in the structure pointed to by buf. The stat() and lstat() functions will fail if: EACCES Search permission is denied for a component of the path prefix. EFAULT The buf or path argument points to an illegal address. EINTR A signal was caught during the execution of the stat() or lstat() function. ELOOP Too many symbolic links were encountered in translat- ing path. ENAMETOOLONG The length of the path argument exceeds PATH_MAX, or the length of a path component exceeds NAME_MAX while _POSIX_NO_TRUNC is in effect. ENOENT The named file does not exist or is the null pathname. SunOS 5.8 Last change: 28 Jan 1998 3 System Calls stat(2) ENOLINK The path argument points to a remote machine and the link to that machine is no longer active. ENOTDIR A component of the path prefix is not a directory. EOVERFLOW A component is too large to store in the structure pointed to by buf. The fstat() function will fail if: EBADF The fildes argument is not a valid open file descrip- tor. EFAULT The buf argument points to an illegal address. EINTR A signal was caught during the execution of the fstat() function. ENOLINK The fildes argument points to a remote machine and the link to that machine is no longer active. EOVERFLOW A component is too large to store in the structure pointed to by buf.

USAGE

The stat(), fstat(), and lstat() functions have transitional interfaces for 64-bit file offsets. See lf64(5).

ATTRIBUTES

See attributes(5) for descriptions of the following attri- butes: ____________________________________________________________ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | | ____________________________|_____________________________|_ | MT-Level | stat() and fstat() are| | | Async-Signal-Safe | |_____________________________|_____________________________|

SEE ALSO

chmod(2), chown(2), creat(2), link(2), mknod(2), pipe(2), read(2), time(2), unlink(2), utime(2), write(2), fattach(3C), attributes(5), lf64(5), stat(3HEAD) SunOS 5.8 Last change: 28 Jan 1998 4 System Calls stat(2)

NOTES

If you use chmod(2) to change the file group owner permis- sions on a file with ACL entries, both the file group owner permissions and the ACL mask are changed to the new permis- sions. Be aware that the new ACL mask permissions may change the effective permissions for additional users and groups who have ACL entries on the file. SunOS 5.8 Last change: 28 Jan 1998 5