.Dd November 8, 2017
.Dt HOLES 1
.Os
.Sh NAME
.Nm holes
.Nd find runs of zero bytes
.Sh SYNOPSIS
.Nm
.Op Fl b Ar byte
.Op Fl n Ar minlen
.Op Fl s
.Op Ar files\ ...
.Sh DESCRIPTION
.Nm
looks for runs of zero bytes (a.k.a. holes) in the specified input files
(or the standard input),
and prints the start addresses (in hexadecimal)
as well as the lengths (in decimal).
When multiple input files are specified,
.Nm
prefixes each line with the file name.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl b Ar byte
Count runs of
.Ar byte ,
a number between 0 and 255,
instead of zero bytes.
.It Fl n Ar minlen
Change minimum size of holes reported.
By default,
only holes of at least 64 bytes are reported.
.It Fl s
Print a summary at the end how many percent of the file are runs of zeroes.
.El
.Sh EXIT STATUS
.Ex -std
.Sh SEE ALSO
.Xr fallocate 1 ,
.Xr truncate 1 ,
.Xr virt-sparsify 1
.Sh AUTHORS
.An Leah Neukirchen Aq Mt leah@vuxu.org
.Sh LICENSE
.Nm
is in the public domain.
.Pp
To the extent possible under law,
the creator of this work
has waived all copyright and related or
neighboring rights to this work.
.Pp
.Lk http://creativecommons.org/publicdomain/zero/1.0/