getbsize(3) [osx man page]

GETBSIZE(3)						   BSD Library Functions Manual 					       GETBSIZE(3)

NAME

     getbsize -- get user block size

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <stdlib.h>

     char *
     getbsize(int *headerlenp, long *blocksizep);

DESCRIPTION

     The getbsize() function determines the user's preferred block size based on the value of the ``BLOCKSIZE'' environment variable; see
     environ(7) for details on its use and format.

     The getbsize() function returns a pointer to a null-terminated string describing the block size, something like ``1K-blocks''.  The memory
     referenced by headerlenp is filled in with the length of the string (not including the terminating null).	The memory referenced by
     blocksizep is filled in with block size, in bytes.

     If the user's block size is unreasonable, a warning message is written to standard error and the returned information reflects a block size
     of 512 bytes.

SEE ALSO

     df(1), du(1), ls(1), systat(1), environ(7)

HISTORY

     The getbsize() function first appeared in 4.4BSD.

BSD
								   June 4, 1993 							       BSD

DU(1)							    BSD General Commands Manual 						     DU(1)

NAME

     du -- display disk usage statistics

SYNOPSIS

     du [-H | -L | -P] [-I mask] [-a | -s | -d depth] [-c] [-h | -k] [-x] [file ...]

DESCRIPTION

     The du utility displays the file system block usage for each file argument and for each directory in the file hierarchy rooted in each direc-
     tory argument.  If no file is specified, the block usage of the hierarchy rooted in the current directory is displayed.  If the -k flag is
     specified, the number of 1024-byte blocks used by the file is displayed, otherwise getbsize(3) is used to determine the preferred block size.
     Partial numbers of blocks are rounded up.

     The options are as follows:

     -H      Symbolic links on the command line are followed, symbolic links in file hierarchies are not followed.

     -L      Symbolic links on the command line and in file hierarchies are followed.

     -I mask
	     Ignore files and directories matching the specified mask.

     -P      No symbolic links are followed.  This is the default.

     -a      Display an entry for each file in a file hierarchy.

     -h      "Human-readable" output.  Use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte

     -r      Generate messages about directories that cannot be read, files that cannot be opened, and so on.  This is the default case.  This
	     option exists solely for conformance with X/Open Portability Guide Issue 4 (``XPG4'').

     -s      Display an entry for each specified file.	(Equivalent to -d 0)

     -d depth
	     Display an entry for all files and directories depth directories deep.

     -c      Display a grand total.

     -k      Display block counts in 1024-byte (1-Kbyte) blocks.

     -x      File system mount points are not traversed.

     The du utility counts the storage used by symbolic links and not the files they reference unless the -H or -L option is specified.  If either
     the -H or -L options are specified, storage used by any symbolic links which are followed is not counted or displayed.

     Files having multiple hard links are counted (and displayed) a single time per du execution.

ENVIRONMENT

     BLOCKSIZE	If the environment variable BLOCKSIZE is set, and the -k option is not specified, the block counts will be displayed in units of
		that size block.  If BLOCKSIZE is not set, and the -k option is not specified, the block counts will be displayed in 512-byte
		blocks.

SEE ALSO

     df(1), fts(3), symlink(7), quot(8)

HISTORY

     A du command appeared in Version 1 AT&T UNIX.

BSD
								   April 1, 1994							       BSD