.\" As its sole author, I explicitly place this file in the public domain.
.\" It may be used by anyone in any way for any purpose, though I would
.\" appreciate credit where it's due.
.\"		der Mouse, mouse@rodents-montreal.org,. 2023-02-14
.Dd Feburary 14, 2023
.Dt TREESUMS 1
.Os NetBSD 1.4T
.Sh NAME
.Nm treesums
.Nd checksum directory trees
.Sh SYNOPSIS
.Nm
.Op options
.Op Ar DIR
.Sh DESCRIPTION
.Nm
computes and prints checksums for the contents of a directory tree.
.Pp
A directory name must be specified, either with no flag
.Pf ( Ar DIR
above) or with
.Fl tree .
.Nm
checksums everything under that directory.  For each filesystem object,
the output records its type, its permission bits, and further data
depending on its type.  Plain files have a checksum printed and
symbolic links have the link-to string printed.  (The checksum for
plain files is, effectively, a concatenation of MD5 and SHA-1 checksums
over the content.)  Timestamps are specifically not included.
Directories are reported in their own right, as well as their contained
objects getting lines of their own.
.Pp
Supported options:
.Bl -tag -width indent
.It Fl tree Ar DIR
The same as specifying
.Ar DIR
unadorned on the commend line, except it's unambiguous if
.Ar dir
begins, or might begin, with a dash.
.It Fl modemask-dir Ar MODE
The permission bits of directories are ANDed with
.Ar MODE
before printing.
.It Fl modemask-reg Ar MODE
The permission bits of regular files are ANDed with
.Ar MODE
before printing.
.It Fl modemask-lnk Ar MODE
The permission bits of symbolic links are ANDed with
.Ar MODE
before printing.
.It Fl modemask Ar MODE
Equivalent to specifying
.Fl modemask-dir ,
.Fl modemask-reg ,
and
.Fl modemask-lnk ,
all with the same
.Ar MODE .
.It Fl cores Ar N
Attempt to parallelize checksumming, using up to
.Ar N
worker processes.  (As the name implies, this is intended to take
advantage of multicore hardware.)
.It Fl h
.It Fl follow
Follow symbolic links, when possible.  A symbolic link that points to
something accessible will be reported as the thing it points to; if it
does not point to anything, or in some cases if the thing it points to
is inaccessible, it will still be reported as a symbolic link (this
just corresponds to the difference between
.Xr stat 2
and
.Xr lstat 2 ) .
.It Fl xdev
Do not cross mount points.  If an object is found whose
.Dv st_dev
differs from that of the main directory, it will be reported with type
character
.Sq x
and will never be descended into, even if it's a directory.
.El
.Sh BUGS
Objects other than directoryes, plain files, and symbolic links should
be handled better.  (At present, they are printed with what would
normally be the type character replaced by a question mark followed by
the relevant st_mode field, with the permission bits forced to zero.)
.Sh AUTHOR
der Mouse,
.Aq mouse@rodents-montreal.org .