Bug#1102095: lwptut.3pm: Some remarks about this man page

Sat Apr 5 00:04:42 BST 2025

Package: libwww-perl
Version: 6.78-1
Severity: minor
Tags: upstream

   * What led up to the situation?

     Checking for defects with a new version

test-[g|n]roff -mandoc -t -K utf8 -rF0 -rHY=0 -rCHECKSTYLE=10 -ww -z < "man page"

  [Use 

grep -n -e ' $' -e '\\~$' -e ' \\f.$' -e ' \\"' <file>

  to find (most) trailing spaces.]

  ["test-groff" is a script in the repository for "groff"; is not shipped]
(local copy and "troff" slightly changed by me).

  [The fate of "test-nroff" was decided in groff bug #55941.]

   * What was the outcome of this action?

troff:<stdin>:150: warning: trailing space in the line
troff:<stdin>:155: warning: trailing space in the line
troff:<stdin>:157: warning: trailing space in the line
troff:<stdin>:160: warning: trailing space in the line
troff:<stdin>:170: warning: trailing space in the line
troff:<stdin>:195: warning: trailing space in the line
troff:<stdin>:229: warning: trailing space in the line
troff:<stdin>:258: warning: trailing space in the line
troff:<stdin>:280: warning: trailing space in the line
troff:<stdin>:281: warning: trailing space in the line
troff:<stdin>:292: warning: trailing space in the line
troff:<stdin>:293: warning: trailing space in the line
troff:<stdin>:296: warning: trailing space in the line
troff:<stdin>:297: warning: trailing space in the line
troff:<stdin>:387: warning: trailing space in the line
troff:<stdin>:392: warning: trailing space in the line
troff:<stdin>:560: warning: trailing space in the line
troff:<stdin>:591: warning: trailing space in the line
troff:<stdin>:770: warning: trailing space in the line

   * What outcome did you expect instead?

     No output (no warnings).

-.-

  General remarks and further material, if a diff-file exist, are in the
attachments.

-- System Information:
Debian Release: trixie/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 6.12.20-amd64 (SMP w/2 CPU threads; PREEMPT)
Locale: LANG=is_IS.iso88591, LC_CTYPE=is_IS.iso88591 (charmap=ISO-8859-1), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages libwww-perl depends on:
ii  ca-certificates             20241223
ii  libencode-locale-perl       1.05-3
ii  libfile-listing-perl        6.16-1
ii  libhtml-parser-perl         3.83-1+b2
ii  libhtml-tagset-perl         3.24-1
ii  libhtml-tree-perl           5.07-3
ii  libhttp-cookies-perl        6.11-1
ii  libhttp-date-perl           6.06-1
ii  libhttp-message-perl        7.00-2
ii  libhttp-negotiate-perl      6.01-2
ii  liblwp-mediatypes-perl      6.04-2
ii  liblwp-protocol-https-perl  6.14-1
ii  libnet-http-perl            6.23-1
ii  libtry-tiny-perl            0.32-1
ii  liburi-perl                 5.30-1
ii  libwww-robotrules-perl      6.02-1
ii  netbase                     6.5
ii  perl                        5.40.1-2

Versions of packages libwww-perl recommends:
pn  libdata-dump-perl    <none>
ii  libhtml-form-perl    6.12-1
ii  libhtml-format-perl  2.16-2
pn  libhttp-daemon-perl  <none>
ii  libmailtools-perl    2.22-1

Versions of packages libwww-perl suggests:
pn  libauthen-ntlm-perl  <none>

-- no debconf information
-------------- next part --------------
Input file is lwptut.3pm

Output from "mandoc -T lint  lwptut.3pm": (shortened list)

      1 input text line longer than 80 bytes: So if we add the fol...
      1 input text line longer than 80 bytes: The actual content o...
      1 input text line longer than 80 bytes: The basic idiom is \...
      1 input text line longer than 80 bytes: The handiest variant...
      1 input text line longer than 80 bytes: To give a browser an...
      1 input text line longer than 80 bytes: When you use this \f...
      1 input text line longer than 80 bytes: a problem with the n...
      1 input text line longer than 80 bytes: and password (at \f(...
      1 input text line longer than 80 bytes: are the \f(CW\*(C`qu...
      1 input text line longer than 80 bytes: by default one minut...
      1 input text line longer than 80 bytes: can use the URI modu...
      1 input text line longer than 80 bytes: documentation, speci...
      1 input text line longer than 80 bytes: environment variable...
      1 input text line longer than 80 bytes: is to use the \f(CW\...
      1 input text line longer than 80 bytes: is with \f(CW\*(C`$u...
      1 input text line longer than 80 bytes: it's a GIF, then \f(...
      1 input text line longer than 80 bytes: its \f(CW\*(C`cookie...
      1 input text line longer than 80 bytes: the \f(CW$browser\fR...
      1 input text line longer than 80 bytes: the \f(CW\*(C`Client...
      1 input text line longer than 80 bytes: versions of LWP, so ...
      1 input text line longer than 80 bytes: won't actually reque...
      1 input text line longer than 80 bytes: you usually call the...
      4 whitespace at end of input line

Find trailing space with:
grep -n -e ' $' -e ' \\f.$' -e ' \\"' <man page>

-.-.

Output from
test-nroff -mandoc -t -ww -z lwptut.3pm: (shortened list)

     19 line(s) with a trailing space

Find trailing space with:
grep -n -e ' $' -e ' \\f.$' -e ' \\"' <man page>

-.-.

Show if Pod::Man generated this.

Who is actually creating this man page?  Debian or upstream?

Is the generating software out of date?

2:.\" Automatically generated by Pod::Man 5.0102 (Pod::Simple 3.45)

-.-.

Remove space characters (whitespace) at the end of lines.
Use "git apply ... --whitespace=fix" to fix extra space issues, or use
global configuration "core.whitespace".

Number of lines affected is

19

-.-.

Strings longer than 3/4 of a standard line length (80).

Use "\:" to split the string at the end of an output line, for example a
long URL (web address)

587 \&  http://www.unicode.org/mail\-arch/unicode\-ml/y2002\-m08/0067.html
602 \&   \*(Aqhttp://www.unicode.org/mail\-arch/unicode\-ml/y2002\-m08/0067.html\*(Aq;
616 \&   at http://www.unicode.org/mail\-arch/unicode\-ml/y2002\-m08/0067.html

-.-.

Wrong distance (not two spaces) between sentences in the input file.

  Separate the sentences and subordinate clauses; each begins on a new
line.  See man-pages(7) ("Conventions for source file layout") and
"info groff" ("Input Conventions").

  The best procedure is to always start a new sentence on a new line,
at least, if you are typing on a computer.

Remember coding: Only one command ("sentence") on each (logical) line.

E-mail: Easier to quote exactly the relevant lines.

Generally: Easier to edit the sentence.

Patches: Less unaffected text.

Search for two adjacent words is easier, when they belong to the same line,
and the same phrase.

  The amount of space between sentences in the output can then be
controlled with the ".ss" request.

Mark a final abbreviation point as such by suffixing it with "\&".

Some sentences (etc.) do not begin on a new line.

Split (sometimes) lines after a punctuation mark; before a conjunction.

  Lines with only one (or two) space(s) between sentences could be split,
so latter sentences begin on a new line.

Use

#!/usr/bin/sh

sed -e '/^\./n' \
-e 's/\([[:alpha:]]\)\.  */\1.\n/g' $1

to split lines after a sentence period.
Check result with the difference between the formatted outputs.
See also the attachment "general.bugs"

68:Perl modules for accessing data on the Web. Like most Perl
70:documentation that is a complete reference to its interface. However,
76:that just happens to exist, called \fIPerl & LWP\fR. But this article
121:\&     | grep "/by\-module/Acme" | mail \-s "New Acme modules! Joy!" $USER
127:saving/mirroring a URL to a local file. See the LWP::Simple
136:error). To get at all those features, you'll have to use the full LWP
140:understand are LWP::UserAgent and HTTP::Response. LWP::UserAgent
181:class HTTP::Response. You really need only one browser object per
214:\&  $response = $browser\->get( $url, $key1, $value1, $key2, $value2, ... );
254:support turned off. There are various ways of turning it on, by setting
255:its \f(CW\*(C`cookie_jar\*(C'\fR attribute. A "cookie jar" is an object representing
257:the HTTP cookies that a browser knows about. It can correspond to a
324:\&  if( $response\->decoded_content =~ m{([0\-9,]+)(?:<.*?>)? results for} ) {
457:and gopher. If it tries accessing any other kind of URL (like an "ftp:"
531:avoid making too many requests too often. How long it will pause for, is
548:accessing certain sites and/or using certain protocols. This is most
571:Authentication". This isn't just any form of "enter your password"
681:\&   Aborting at paypal.pl line 7.   [or whatever program and line]
695:memory will have to hold the whole document \-\- \fIin memory\fR. If the
764:(like turning "C. & E. Bront??" to and from "C. & E. Brontë")
770:The book \fIPerl & LWP\fR by Sean M. Burke.  O'Reilly & Associates, 
776:Copyright 2002, Sean M. Burke.  You can redistribute this document and/or
780:Sean M. Burke \f(CW\*(C`sburke at cpan.org\*(C'\fR

-.-.

Split lines longer than 80 characters into two or more lines.
Appropriate break points are the end of a sentence and a subordinate
clause; after punctuation marks.
Add "\:" to split the string for the output, "\<newline>" in the source.  

[List of affected lines removed.]

Longest line is number 367 with 158 characters
is with \f(CW\*(C`$url\->scheme\*(C'\fR, and asking what host it refers to with \f(CW\*(C`$url\->host\*(C'\fR, and so on, as described in the docs for the URI

-.-.

Do not use more than two space characters between sentences or (better)
only a new line character.

681:\&   Aborting at paypal.pl line 7.   [or whatever program and line]

-.-.

Add a zero (0) in front of a decimal fraction that begins with a period
(.)

7:.if t .sp .5v

-.-.

Test nr. 63:

Put a parenthetical sentence, phrase on a separate line,
if not part of a code.
See man-pages(7), item "semantic newline".

[List of affected lines removed.]

-.-

Use a character "\(->" instead of plain "->" or "\->".

[List of affected lines removed.]

-.-

Only one space character is after a possible end of sentence
(after a punctuation, that can end a sentence).

[List of affected lines removed.]

-.-.

Put a subordinate sentence (after a comma) on a new line.

[List of affected lines removed.]

-.-.

Use ".na" (no adjustment) instead of ".ad l" (and ".ad" to begin the
same adjustment again as before).

61:.if n .ad l

-.-.

Add lines to use the CR font for groff instead of CW.

.if t \{\
.  ie \\n(.g .ft CR
.  el .ft CW
.\}

11:.ft CW

-.-.

Section headings (.SH and .SS) do not need quoting their arguments.

79:.SS "Getting documents with LWP::Simple"
130:.SS "The Basics of the LWP Class Model"
206:.SS "Adding Other HTTP Request Headers"
251:.SS "Enabling Cookies"
272:.SS "Posting Form Data"
332:.SS "Sending GET Form Data"
363:.SS "Absolutizing URLs"
444:.SS "Other Browser Attributes"
494:.SS "Writing Polite Robots"
545:.SS "Using Proxies"
568:.SS "HTTP Authentication"
658:.SS "Accessing HTTPS URLs"
691:.SS "Getting Large Documents"
740:.SH "SEE ALSO"

-.-.

.\" Define a fallback for font CW with

.if t \{\
.  ie \n(.g .ds fC \f(CR
.  el .ds fC \f(CW
.  ds fP \fP
.\}
.
.if n \{\
.  ds fC \fR
.  ds fP \fP
.\}

[List of affected lines removed.]

-.-.

Output from "test-groff  -mandoc -t -K utf8 -rF0 -rHY=0 -rCHECKSTYLE=10 -ww -z ":

troff:<stdin>:150: warning: trailing space in the line
troff:<stdin>:155: warning: trailing space in the line
troff:<stdin>:157: warning: trailing space in the line
troff:<stdin>:160: warning: trailing space in the line
troff:<stdin>:170: warning: trailing space in the line
troff:<stdin>:195: warning: trailing space in the line
troff:<stdin>:229: warning: trailing space in the line
troff:<stdin>:258: warning: trailing space in the line
troff:<stdin>:280: warning: trailing space in the line
troff:<stdin>:281: warning: trailing space in the line
troff:<stdin>:292: warning: trailing space in the line
troff:<stdin>:293: warning: trailing space in the line
troff:<stdin>:296: warning: trailing space in the line
troff:<stdin>:297: warning: trailing space in the line
troff:<stdin>:387: warning: trailing space in the line
troff:<stdin>:392: warning: trailing space in the line
troff:<stdin>:560: warning: trailing space in the line
troff:<stdin>:591: warning: trailing space in the line
troff:<stdin>:770: warning: trailing space in the line

-.-.

Generally:

Split (sometimes) lines after a punctuation mark; before a conjunction.
-------------- next part --------------
  Any program (person), that produces man pages, should check the output
for defects by using (both groff and nroff)

[gn]roff -mandoc -t -ww -b -z -K utf8 <man page>

  To find trailing space use

grep -n -e ' $' -e ' \\f.$' -e ' \\"' <man page>

  The same goes for man pages that are used as an input.

  For a style guide use

  mandoc -T lint

-.-

  Any "autogenerator" should check its products with the above mentioned
'groff', 'mandoc', and additionally with 'nroff ...'.

  It should also check its input files for too long (> 80) lines.

  This is just a simple quality control measure.

  The "autogenerator" may have to be corrected to get a better man page,
the source file may, and any additional file may.

  Common defects:

  Not removing trailing spaces (in in- and output).
  The reason for these trailing spaces should be found and eliminated.

  "git" has a "tool" to point out whitespace,
see for example "git-apply(1)" and git-config(1)")

  Not beginning each input sentence on a new line.
Line length and patch size should thus be reduced.

  The script "reportbug" uses 'quoted-printable' encoding when a line is
longer than 1024 characters in an 'ascii' file.

  See man-pages(7), item "semantic newline".

-.-

The difference between the formatted output of the original and patched file
can be seen with:

  nroff -mandoc <file1> > <out1>
  nroff -mandoc <file2> > <out2>
  diff -d -u <out1> <out2>

and for groff, using

\"printf '%s\n%s\n' '.kern 0' '.ss 12 0' | groff -mandoc -Z - \"

instead of 'nroff -mandoc'

  Add the option '-t', if the file contains a table.

  Read the output from 'diff -d -u ...' with 'less -R' or similar.

-.-.

  If 'man' (man-db) is used to check the manual for warnings,
the following must be set:

  The option "-warnings=w"

  The environmental variable:

export MAN_KEEP_STDERR=yes (or any non-empty value)

  or

  (produce only warnings):

export MANROFFOPT="-ww -b -z"

export MAN_KEEP_STDERR=yes (or any non-empty value)

-.-