xref: /freebsd/lib/libc/gen/getbsize.3 (revision 17ee9d00bc1ae1e598c38f25826f861e4bc6c3ce)
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32.\"     @(#)getbsize.3	8.1 (Berkeley) 6/4/93
33.\"
34.Dd June 4, 1993
35.Dt GETBSIZE 3
36.Os BSD 4.4
37.Sh NAME
38.Nm getbsize
39.Nd get user block size
40.Sh SYNOPSIS
41.Fd #include <stdlib.h>
42.Ft char *
43.Fn getbsize "int *headerlenp" "long *blocksizep"
44.Sh DESCRIPTION
45The
46.Nm getbsize
47function determines the user's preferred block size based on the value of the
48.Dq BLOCKSIZE
49environment variable; see
50.Xr environ 7
51for details on its use and format.
52.Pp
53The
54.Nm getbsize
55function returns a pointer to a null-terminated string describing
56the block size, something like
57.Dq 1K-blocks .
58The memory referenced by
59.Fa headerlenp
60is filled in with the length of the string (not including the
61terminating null).
62The memory referenced by
63.Fa blocksizep
64is filled in with block size, in bytes.
65.Pp
66If the user's block size is unreasonable, a warning message is
67written to standard error and the returned information reflects
68a block size of 512 bytes.
69.Sh SEE ALSO
70.Xr df 1 ,
71.Xr du 1 ,
72.Xr ls 1 ,
73.Xr systat 1 ,
74.Xr environ 7
75.Sh HISTORY
76The
77.Nm getbsize
78function call appeared in
79.Bx 4.4 .
80