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 NUL terminated string describing the block size, something like ``1K-blocks''. If the
headerlenp parameter is not NULL the memory referenced by headerlenp is filled in with the length of the string (not including the terminat-
ing NUL). If the blocksizep parameter is not 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 May 30, 2003 BSD
Check Out this Related Man Page
DU(1) BSD General Commands Manual DU(1)NAME
du -- display disk usage statistics
SYNOPSIS
du [-H | -L | -P] [-a | -d depth | -s] [-cghkmnrx] [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.
The options are as follows:
-H Symbolic links on the command line are followed. (Symbolic links encountered in the tree traversal are not followed.)
-L All symbolic links are followed.
-P No symbolic links are followed.
-a Display an entry for each file in the file hierarchy.
-c Display the grand total after all the arguments have been processed.
-d Display an entry files and directories depth directories deep.
-g If the -g flag is specified, the number displayed is the number of gigabyte (1024*1024*1024 bytes) blocks.
-h If the -h flag is specified, the numbers will be displayed in "human-readable" format. Use unit suffixes: B (Byte), K (Kilobyte), M
(Megabyte), G (Gigabyte), T (Terabyte) and P (Petabyte).
-k By default, du displays the number of blocks as returned by the stat(2) system call, i.e. 512-byte blocks. If the -k flag is speci-
fied, the number displayed is the number of kilobyte (1024 bytes) blocks. Partial numbers of blocks are rounded up.
-m If the -m flag is specified, the number displayed is the number of megabyte (1024*1024 bytes) blocks.
-n Ignore files and directories with user "nodump" flag (UF_NODUMP) set.
-r Generate warning messages about directories that cannot be read. This is the default behaviour.
-s Display only the grand total for the specified files.
-x Filesystem mount points are not traversed.
du 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. The -H, -L and -P options over-
ride each other and the command's actions are determined by the last one specified.
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 -g, -h, -k, and -m options are not specified, the block counts will be dis-
played in units of that size block.
SEE ALSO df(1), chflags(2), fts(3), getbsize(3), symlink(7), quot(8)HISTORY
A du command appeared in Version 6 AT&T UNIX.
BSD September 24, 2006 BSD