FSTAT(3P)						     POSIX Programmer's Manual							 FSTAT(3P)

PROLOG

       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

       fstat - get file status

SYNOPSIS

       #include <sys/stat.h>

       int fstat(int fildes, struct stat *buf);

DESCRIPTION

       The fstat() function shall obtain information about an open file associated with the file descriptor fildes, and shall write it to the area
       pointed to by buf.

       If  fildes references a shared memory object, the implementation shall update in the stat structure pointed to by the buf argument only the
       st_uid, st_gid, st_size, and st_mode fields, and only the S_IRUSR, S_IWUSR, S_IRGRP, S_IWGRP, S_IROTH, and  S_IWOTH  file  permission  bits
       need be valid. The implementation may update other fields and flags.

       If  fildes  references a typed memory object, the implementation shall update in the stat structure pointed to by the buf argument only the
       st_uid, st_gid, st_size, and st_mode fields, and only the S_IRUSR, S_IWUSR, S_IRGRP, S_IWGRP, S_IROTH, and  S_IWOTH  file  permission  bits
       need be valid. The implementation may update other fields and flags.

       The buf argument is a pointer to a stat structure, as defined in <sys/stat.h>, into which information is placed concerning the file.

       The  structure members st_mode, st_ino, st_dev, st_uid, st_gid, st_atime, st_ctime, and st_mtime shall have meaningful values for all other
       file types defined in this volume of IEEE Std 1003.1-2001. The value of the member st_nlink shall be set to the	number	of  links  to  the
       file.

       An  implementation  that  provides  additional  or alternative file access control mechanisms may, under implementation-defined conditions,
       cause fstat() to fail.

       The fstat() function shall update any time-related fields as described in the Base Definitions volume of IEEE Std 1003.1-2001, Section 4.7,
       File Times Update, before writing into the stat structure.

RETURN VALUE

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

ERRORS

       The fstat() function shall fail if:

       EBADF  The fildes argument is not a valid file descriptor.

       EIO    An I/O error occurred while reading from the file system.

       EOVERFLOW
	      The  file  size  in bytes or the number of blocks allocated to the file or the file serial number cannot be represented correctly in
	      the structure pointed to by buf.

       The fstat() function may fail if:

       EOVERFLOW
	      One of the values is too large to store into the structure pointed to by the buf argument.

       The following sections are informative.

EXAMPLES

   Obtaining File Status Information
       The following example shows how to obtain file status information for a file named /home/cnd/mod1. The structure variable buffer is defined
       for the stat structure. The /home/cnd/mod1 file is opened with read/write privileges and is passed to the open file descriptor fildes.

	      #include <sys/types.h>
	      #include <sys/stat.h>
	      #include <fcntl.h>

	      struct stat buffer;
	      int	  status;
	      ...
	      fildes = open("/home/cnd/mod1", O_RDWR);
	      status = fstat(fildes, &buffer);

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       lstat(), stat(), the Base Definitions volume of IEEE Std 1003.1-2001, <sys/stat.h>, <sys/types.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
       Electrical  and	Electronics  Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE
       and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can  be  obtained
       online at http://www.opengroup.org/unix/online.html .

IEEE
/The Open Group						       2003								 FSTAT(3P)