From "man ..." ("groff -ww ..."):

/home/bg/opt/share/groff/1.21/tmac/an-ext.tmac:195: backtrace: macro `EE'
<groff: zipinfo.1>:349: warning: number register `mE' not defined
/home/bg/opt/share/groff/1.21/tmac/an-ext.tmac:195: backtrace: macro `EE'
<groff: zipinfo.1>:349: warning: bad font number
<groff: zipinfo.1>:469: warning: escape character ignored before `+'
<groff: zipinfo.1>:470: warning: escape character ignored before `+'

  Some minor cosmetic corrections.

  Some general remarks:

a) Manuals should usually only be left justified.  Use ".ad l"
as the first regular command.

b) Each sentence should begin on a new line.  The conventions
about the amount of space between sentences are different.  This
also makes a check on the number of space characters between
words easier.

c) Separate numbers from units with a (no-break) space.  A
no-break space can be code 0xA0, "\ " (\<space>), or "\~"
(groff).

d) Use macros "TS/TE" for tables with more than two columns.
Then use

'\" t

as the first line in the source to tell "man" to use the "tbl"
preprocessor.

e) Protect the last period (full stop) (before space or end of
line) in abbreviations or ellipsis with "\&", if it is or might be
(through new formatting of source) at the end of line, if it is
also not an end of sentence.

f) Use "\-" for options

g)  Use "\-" or an en-dash ("\(en") for the word "to", as in "1 to
3" (1\-3).


  Patch:
--- zipinfo.1	2012-06-22 02:32:41.000000000 +0000
+++ zipinfo.1.new	2012-06-22 03:44:32.000000000 +0000
@@ -151,7 +151,7 @@
 their uncompressed and compressed total sizes , and their overall compression
 factor is printed; or, if only the totals line is being printed, the values
 for the entire archive are given.  The compressed total size does not include
-the 12 additional header bytes of each encrypted entry. Note that the total
+the 12 additional header bytes of each encrypted entry.  Note that the total
 compressed (data) size will never match the actual zipfile size, since the
 latter includes all of the internal zipfile headers in addition to the
 compressed data.
@@ -346,7 +346,6 @@
 .TP
 VMS (quotes for \fIlowercase\fP):
 \f(CW\&define ZIPINFO_OPTS "\-l"\fP
-.EE
 .PP
 If, in addition, the user dislikes the trailer line, \fIzipinfo\fP's
 concept of ``negative options'' may be used to override the default
@@ -457,7 +456,7 @@
 such as Unix \fIsort\fP(1) (and \fIsed\fP(1) as well, in this example):
 .PP
 .EX
-zipinfo \-T storage | sort -nr -k 7 | sed 15q
+zipinfo \-T storage | sort \-nr \-k 7 | sed 15q
 .EE
 .PP
 The \fB\-nr\fP option to \fIsort\fP(1) tells it to sort numerically
@@ -466,8 +465,8 @@
 assumes the default short-listing format; if \fB\-m\fP or \fB\-l\fP is
 used, the proper \fIsort\fP(1) option would be \fB\-k\ 8\fP.
 Older versions of \fIsort\fP(1) do not support the \fB\-k\fP option,
-but you can use the traditional \fB\+\fP option instead, e.g.,
-\fB\+6\fP instead of \fB\-k\ 7\fP.  The \fIsed\fP(1)
+but you can use the traditional \fB+\fP option instead, e.g.,
+\fB+6\fP instead of \fB\-k\ 7\fP.  The \fIsed\fP(1)
 command filters out all but the first 15 lines of the listing.  Future
 releases of \fIzipinfo\fP may incorporate date/time and filename sorting
 as built-in options.