add directory Minix

This commit is contained in:
gohigh
2024-02-19 00:21:39 -05:00
parent 56596ada90
commit 5a46ddb732
2923 changed files with 1764412 additions and 0 deletions

View File

@@ -0,0 +1,65 @@
<HTML>
<HEAD>
<TITLE>ascii(7)</TITLE>
</HEAD>
<BODY>
<H1>ascii(7)</H1>
<HR>
<PRE>
</PRE>
<H2>NAME</H2><PRE>
ascii - the ASCII character set.
</PRE>
<H2>DESCRIPTION</H2><PRE>
The ASCII character set is as follows:
|000 nul|001 soh|002 stx|003 etx|004 eot|005 enq|006 ack|007 bel|
|010 bs |011 ht |012 nl |013 vt |014 np |015 cr |016 so |017 si |
|020 dle|021 dc1|022 dc2|023 dc3|024 dc4|025 nak|026 syn|027 etb|
|030 can|031 em |032 sub|033 esc|034 fs |035 gs |036 rs |037 us |
|040 sp |041 ! |042 " |043 # |044 $ |045 % |046 &amp; |047 ' |
|050 ( |051 ) |052 * |053 + |054 , |055 - |056 . |057 / |
|060 0 |061 1 |062 2 |063 3 |064 4 |065 5 |066 6 |067 7 |
|070 8 |071 9 |072 : |073 ; |074 &lt; |075 = |076 &gt; |077 ? |
|100 @ |101 A |102 B |103 C |104 D |105 E |106 F |107 G |
|110 H |111 I |112 J |113 K |114 L |115 M |116 N |117 O |
|120 P |121 Q |122 R |123 S |124 T |125 U |126 V |127 W |
|130 X |131 Y |132 Z |133 [ |134 \ |135 ] |136 ^ |137 _ |
|140 ` |141 a |142 b |143 c |144 d |145 e |146 f |147 g |
|150 h |151 i |152 j |153 k |154 l |155 m |156 n |157 o |
|160 p |161 q |162 r |163 s |164 t |165 u |166 v |167 w |
|170 x |171 y |172 z |173 { |174 | |175 } |176 ~ |177 del|
|00 nul|01 soh|02 stx|03 etx|04 eot|05 enq|06 ack|07 bel|
|08 bs |09 ht |0A nl |0B vt |0C np |0D cr |0E so |0F si |
|10 dle|11 dc1|12 dc2|13 dc3|14 dc4|15 nak|16 syn|17 etb|
|18 can|19 em |1A sub|1B esc|1C fs |1D gs |1E rs |1F us |
|20 sp |21 ! |22 " |23 # |24 $ |25 % |26 &amp; |27 ' |
|28 ( |29 ) |2A * |2B + |2C , |2D - |2E . |2F / |
|30 0 |31 1 |32 2 |33 3 |34 4 |35 5 |36 6 |37 7 |
|38 8 |39 9 |3A : |3B ; |3C &lt; |3D = |3E &gt; |3F ? |
|40 @ |41 A |42 B |43 C |44 D |45 E |46 F |47 G |
|48 H |49 I |4A J |4B K |4C L |4D M |4E N |4F O |
|50 P |51 Q |52 R |53 S |54 T |55 U |56 V |57 W |
|58 X |59 Y |5A Z |5B [ |5C \ |5D ] |5E ^ |5F _ |
|60 ` |61 a |62 b |63 c |64 d |65 e |66 f |67 g |
|68 h |69 i |6A j |6B k |6C l |6D m |6E n |6F o |
|70 p |71 q |72 r |73 s |74 t |75 u |76 v |77 w |
|78 x |79 y |7A z |7B { |7C | |7D } |7E ~ |7F del|
</PRE>
</BODY>
</HTML>

View File

@@ -0,0 +1,119 @@
<HTML>
<HEAD>
<TITLE>environ(7)</TITLE>
</HEAD>
<BODY>
<H1>environ(7)</H1>
<HR>
<PRE>
</PRE>
<H2>NAME</H2><PRE>
environ - user environment
</PRE>
<H2>SYNOPSIS</H2><PRE>
<STRONG>extern</STRONG> <STRONG>char</STRONG> <STRONG>*const</STRONG> <STRONG>*environ;</STRONG>
</PRE>
<H2>DESCRIPTION</H2><PRE>
An array of strings called the `environment' is made available by
<STRONG><A HREF="../man2/execve.2.html">execve(2)</A></STRONG> when a process begins. By convention these strings have the
form `<EM>name</EM>=<EM>value</EM>'. The following names are used by various commands:
<STRONG>PATH</STRONG> The sequence of directory prefixes that <STRONG>sh</STRONG>, <STRONG>time</STRONG>, <STRONG><A HREF="../man1/nice.1.html">nice(1)</A></STRONG>, etc.,
apply in searching for a file known by an incomplete path name.
The prefixes are separated by `:'. Login shells set
<STRONG>PATH=:/bin:/usr/bin</STRONG>. Note that the empty space between the `='
and the `:' indicates the current directory. Security aware
people move the extra `:' to the end of their path or omit it.
<STRONG>HOME</STRONG> A user's login directory, set by <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG> from the password file
<STRONG><A HREF="../man5/passwd.5.html">passwd(5)</A></STRONG>.
<STRONG>TERM</STRONG> The kind of terminal for which output is to be prepared. This
information is used by programs that wish to exploit special
terminal capabilities, a screen oriented text editor for
instance. The terminal type is set by <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG> from the tty
database <STRONG><A HREF="../man5/ttytab.5.html">ttytab(5)</A></STRONG>.
<STRONG>SHELL</STRONG> The file name of the users login shell, set by <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG> from the
password file <STRONG><A HREF="../man5/passwd.5.html">passwd(5)</A></STRONG>.
<STRONG>TERMCAP</STRONG> The string describing the terminal in TERM, or the name of the
termcap file, see <STRONG><A HREF="../man5/termcap.5.html">termcap(5)</A></STRONG>, <STRONG><A HREF="../man3/termcap.3.html">termcap(3)</A></STRONG>.
<STRONG>EXINIT</STRONG> A startup list of commands read by <STRONG><A HREF="../man1/elvis.1.html">elvis(1)</A></STRONG>.
<STRONG>USER</STRONG> The login name of the user, set by <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG> from the password
file <STRONG><A HREF="../man5/passwd.5.html">passwd(5)</A></STRONG>.
<STRONG>LOGNAME</STRONG> Set to the same value as <STRONG>USER</STRONG>. BSD derived systems have <STRONG>USER</STRONG>,
System V has <STRONG>LOGNAME</STRONG>, so modern systems have both to avoid
problems.
Further names may be placed in the environment by the <STRONG>export</STRONG> command and
`<EM>name</EM>=<EM>value</EM>' arguments in <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG>. Arguments may also be placed in their
environment by programs if they use <STRONG><A HREF="../man3/putenv.3.html">putenv(3)</A></STRONG>. Or in the environment of
another program by building a new environment for one of the exec
functions that accepts an environment list, like <STRONG><A HREF="../man2/execle.2.html">execle(2)</A></STRONG> or <STRONG><A HREF="../man2/execve.2.html">execve(2)</A></STRONG>.
It is unwise to conflict with certain <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG> variables that are frequently
set and/or exported by `.profile' files: <STRONG>MAIL</STRONG>, <STRONG>PS1</STRONG>, <STRONG>PS2</STRONG>, <STRONG>IFS</STRONG>.
</PRE>
<H2>SEE ALSO</H2><PRE>
<STRONG><A HREF="../man1/elvis.1.html">elvis(1)</A></STRONG>, <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG>, <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG>, <STRONG><A HREF="../man2/execl.2.html">execl(2)</A></STRONG>, <STRONG><A HREF="../man2/execve.2.html">execve(2)</A></STRONG>, <STRONG><A HREF="../man3/system.3.html">system(3)</A></STRONG>, <STRONG><A HREF="../man3/termcap.3.html">termcap(3)</A></STRONG>,
<STRONG><A HREF="../man5/termcap.5.html">termcap(5)</A></STRONG>, <STRONG><A HREF="../man5/ttytab.5.html">ttytab(5)</A></STRONG>.
</PRE>
</BODY>
</HTML>

View File

@@ -0,0 +1,224 @@
<HTML>
<HEAD>
<TITLE>hier(7)</TITLE>
</HEAD>
<BODY>
<H1>hier(7)</H1>
<HR>
<PRE>
</PRE>
<H2>NAME</H2><PRE>
hier - file system hierarchy
</PRE>
<H2>DESCRIPTION</H2><PRE>
A tour through the Minix directory hierarchy.
/ root
/bin/ Utility programs, cf /usr/bin/ (1)
cat Show files, <STRONG><A HREF="../man1/cat.1.html">cat(1)</A></STRONG>
sh Shell, <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG>
mount Mount file systems, <STRONG><A HREF="../man8/mount.8.html">mount(8)</A></STRONG>
...
/boot Boot Monitor, <STRONG><A HREF="../man8/monitor.8.html">monitor(8)</A></STRONG>
/dev/ devices (4)
console
Main console, <STRONG><A HREF="../man4/tty.4.html">tty(4)</A></STRONG>
tty* Terminals, <STRONG><A HREF="../man4/tty.4.html">tty(4)</A></STRONG>
hd* Hard disk, <STRONG><A HREF="../man4/hd.4.html">hd(4)</A></STRONG>
fd* Floppy disk, <STRONG><A HREF="../man4/fd.4.html">fd(4)</A></STRONG>
...
/etc/ System configuration and data files, cf /usr/etc/ (1,5,8)
ethers Ethernet addresses database, <STRONG><A HREF="../man5/ethers.5.html">ethers(5)</A></STRONG>
fstab File system table, <STRONG><A HREF="../man5/fstab.5.html">fstab(5)</A></STRONG>
group Groups database, <STRONG><A HREF="../man5/group.5.html">group(5)</A></STRONG>
hostname.file
Name of the local system, <STRONG><A HREF="../man5/usage.5.html">usage(5)</A></STRONG>
hosts TCP/IP hosts database, <STRONG><A HREF="../man5/hosts.5.html">hosts(5)</A></STRONG>
hosts.equiv
Network equivalent hosts, <STRONG><A HREF="../man5/hosts.equiv.5.html">hosts.equiv(5)</A></STRONG>
keymap Keymap for custom keyboard, <STRONG><A HREF="../man8/loadkeys.8.html">loadkeys(8)</A></STRONG>
motd Message of the day, <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG>
mtab Mounted file system table, <STRONG><A HREF="../man5/fstab.5.html">fstab(5)</A></STRONG>
passwd User database, <STRONG><A HREF="../man5/passwd.5.html">passwd(5)</A></STRONG>
psdatabase
Kernel info for ps command, <STRONG><A HREF="../man1/ps.1.html">ps(1)</A></STRONG>
profile
System wide shell profile, <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG>
rc System startup script, <STRONG><A HREF="../man8/boot.8.html">boot(8)</A></STRONG>
resolv.conf
TCP/IP domain name system, <STRONG><A HREF="../man5/resolv.conf.5.html">resolv.conf(5)</A></STRONG>
services
TCP/IP names to services, <STRONG><A HREF="../man5/services.5.html">services(5)</A></STRONG>
shadow Shadow password database, <STRONG><A HREF="../man5/passwd.5.html">passwd(5)</A></STRONG>
termcap
Terminal type descriptions, <STRONG><A HREF="../man5/termcap.5.html">termcap(5)</A></STRONG>
ttys Active terminals, <STRONG><A HREF="../man8/init.8.html">init(8)</A></STRONG>
ttytype
Terminal types, <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG>
utmp User login database, <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG>
...
/minix
Minix kernel image, <STRONG><A HREF="../man8/monitor.8.html">monitor(8)</A></STRONG>
/tmp/ Small, short-lived temporary files, cf /usr/tmp/
/usr/ Home directories and more system files
adm/ System administration files (1,5,8)
wtmp
User logins and logouts, <STRONG><A HREF="../man1/login.1.html">login(1)</A></STRONG>
...
ast/ Honorary home directory of Andrew S. Tanenbaum
Also new user initial files
<EM>user</EM>/ Home directory of <EM>user</EM>
.ashrc Ash (shell) startup, <STRONG><A HREF="../man1/ash.1.html">ash(1)</A></STRONG>
.ellepro.b1
Elle (editor) startup (compiled), <STRONG><A HREF="../man1/elle.1.html">elle(1)</A></STRONG>
.ellepro.e
Elle (editor) startup (text), <STRONG><A HREF="../man1/elle.1.html">elle(1)</A></STRONG>
.exrc Ex/vi (editor) startup, <STRONG><A HREF="../man1/ex.1.html">ex(1)</A></STRONG>
.profile
Custom user shell profile, <STRONG><A HREF="../man1/sh.1.html">sh(1)</A></STRONG>
.rhosts Remote user permission file, <STRONG><A HREF="../man5/rhosts.5.html">rhosts(5)</A></STRONG>
...
bin/ User programs
cc C compiler, <STRONG><A HREF="../man1/cc.1.html">cc(1)</A></STRONG>
cp Copy files, <STRONG><A HREF="../man1/cp.1.html">cp(1)</A></STRONG>
ls List files, <STRONG><A HREF="../man1/ls.1.html">ls(1)</A></STRONG>
man Show manual pages, <STRONG><A HREF="../man1/man.1.html">man(1)</A></STRONG>
...
etc/ More system data files, cf /etc (8)
...
include/
C-compiler include files
minix/ Minix kernel include files
...
...
lib/ Compiler libraries and other support stuff
cawf/ Text formatter support files, <STRONG><A HREF="../man1/cawf.1.html">cawf(1)</A></STRONG>
crontab
Cron jobs, <STRONG><A HREF="../man8/cron.8.html">cron(8)</A></STRONG>
dict/ Word lists
words American English word list, <STRONG><A HREF="../man1/look.1.html">look(1)</A></STRONG>
...
libc.a C library (Minix-8086 only), <STRONG><A HREF="../man1/cc.1.html">cc(1)</A></STRONG>
<EM>arch</EM> Per architecture compiler binaries and
libaries, <STRONG><A HREF="../man1/cc.1.html">cc(1)</A></STRONG>
...
local/ Local software, cf /usr/
bin/ Local utilities
man/ Local manual pages
src/ Local sources
...
man/ Manual pages, <STRONG><A HREF="../man1/man.1.html">man(1)</A></STRONG>
cat*/ Preformatted manual pages
man0/ Section 0, Book style user commands
man1/ User commands
man2/ System calls
man3/ Library routines
man4/ Device files
man5/ File formats
man6/ Games
man7/ Miscellaneous
man8/ System utilities
whatis Table of manual pages, <STRONG><A HREF="../man5/whatis.5.html">whatis(5)</A></STRONG>
...
mdec/
boot Bootstrap code, <STRONG><A HREF="../man8/installboot.8.html">installboot(8)</A></STRONG>
...
preserve/
Saved elvis editor buffers, <STRONG><A HREF="../man8/elvprsv.8.html">elvprsv(8)</A></STRONG>, <STRONG><A HREF="../man1/elvrec.1.html">elvrec(1)</A></STRONG>
spool/ Mail and command spooling
at/ At jobs, <STRONG><A HREF="../man1/at.1.html">at(1)</A></STRONG>
past/ Completed at jobs
mail/ Mail drops, <STRONG><A HREF="../man1/mail.1.html">mail(1)</A></STRONG>
<EM>user</EM> Mailbox of <EM>user</EM>
...
...
src/ System and command sources (home of bin)
LICENSE
Minix license to use
commands/
Utility sources
crclist
CRC checksums of the source tree, <STRONG><A HREF="../man8/srccrc.8.html">srccrc(8)</A></STRONG>
lib/ Library sources
fs/ File system
inet/ TCP/IP task
kernel/
Kernel
mm/ Memory manager
boot/ Boot Monitor
tools/ Kernel image making tools, <STRONG><A HREF="../man8/tools.8.html">tools(8)</A></STRONG>
tmp/ Large temporary files
</PRE>
<H2>SEE ALSO</H2><PRE>
<STRONG><A HREF="../man1/ls.1.html">ls(1)</A></STRONG>, <STRONG><A HREF="../man1/man.1.html">man(1)</A></STRONG>, <STRONG><A HREF="../man1/find.1.html">find(1)</A></STRONG>, <STRONG><A HREF="../man1/grep.1.html">grep(1)</A></STRONG>, <STRONG><A HREF="../man8/checkhier.8.html">checkhier(8)</A></STRONG>.
</PRE>
<H2>NOTES</H2><PRE>
Not all of the directories and files shown are present. They must be
created as needed.
</PRE>
<H2>BUGS</H2><PRE>
Many of the listed manual references do not yet exist.
</PRE>
<H2>AUTHOR</H2><PRE>
Kees J. Bot (kjb@cs.vu.nl)
</PRE>
</BODY>
</HTML>

View File

@@ -0,0 +1,281 @@
<HTML>
<HEAD>
<TITLE>man(7)</TITLE>
</HEAD>
<BODY>
<H1>man(7)</H1>
<HR>
<PRE>
</PRE>
<H2>NAME</H2><PRE>
man - nroff macro package for manual pages
</PRE>
<H2>SYNOPSIS</H2><PRE>
<STRONG>nroff</STRONG> <STRONG>-man</STRONG> <EM>file</EM> ...
</PRE>
<H2>DESCRIPTION</H2><PRE>
These macros are used to lay out reference pages for manuals.
Any text argument <EM>t</EM> may be zero to six words. Quotes may be used to
include blanks in a 'word'. <EM>Text</EM> can be empty, but unlike normal UNIX
macros, the next line is not used.
A prevailing indent distance is remembered between successive indented
paragraphs, and is reset to default value upon reaching a non-indented
paragraph (i.e. at .SH or .SS).
</PRE>
<H2>FILES</H2><PRE>
/usr/lib/tmac/tmac.an For standard Minix nroff.
/usr/lib/cawf/man.mac For cawf.
</PRE>
<H2>SEE ALSO</H2><PRE>
<STRONG><A HREF="../man1/nroff.1.html">nroff(1)</A></STRONG>, <STRONG><A HREF="../man1/man.1.html">man(1)</A></STRONG>.
</PRE>
<H2>REQUEST SUMMARY</H2><PRE>
Request Cause Explanation
Break?
.B t no Text t is bold. Quote to imbed blanks.
.I t no Text t is italic. Quote to imbed blanks.
.IP x yes Set prevailing indent to 5. Begin
indented paragraph with hanging tag
given by first argument. Tag x is
always placed on a separate line.
.LP yes Same as .PP.
.PP yes Begin paragraph. Set prevailing
indent to 5.
.RE yes End of relative indent. Set prevailing
indent to amount of starting .RS.
.RS yes Start relative indent, move left margin
in distance 5.
.SH t yes Subhead. Quote to imbed blanks.
.SS t yes Subsection. Quote to imbed blanks. No
indent for t.
.TH n s c v d yes Begin page named n of chapter s; c is
the chapter name; d is the date of the
most recent change; v is version number.
Sets prevailing indent and tabs to 5.
</PRE>
<H2>EXAMPLE</H2><PRE>
The following illustrates some of the requests available with this macro
package:
.\" this is a comment
.TH DEMO 1
.SH NAME
demo \- show how to use \-man package
.SH SYNOPSIS
.B demo
.RI [ options ]
.IR file " ..."
.SH DESCRIPTION
This is a test for showing how to use the
.BR nroff (1)
man package. It shows how to use .TH, .SH, .PP, .B, .I, and .IP
commands.
.PP
This will be a new paragraph. You can also use normal
.BR nroff (1)
commands in the text.
.SS Nroff Commands
.IP '\e"'
This is the comment command. \" You won't see this.
.IP nf
No fill mode (the normal mode is fill mode where things
get justified right and left).
.IP fi
Re-enter fill mode.
.IP br
Break line here no matter what.
.IP sp
Vertical space (also causes a break to occur).
.sp
Note that to continue an indent and make a new paragraph (as
is the case here), just put in a space (.sp).
.PP
Now we should be at a new paragraph.
Executing <STRONG>nroff</STRONG> <STRONG>-man</STRONG> <STRONG>demo.man</STRONG> results in the following output: (Ignoring
page headers and footers)
<STRONG>NAME</STRONG>
demo \- show how to use \-man package
<STRONG>SYNOPSIS</STRONG>
<STRONG>demo</STRONG> [<EM>options</EM>] <EM>file</EM> ...
<STRONG>DESCRIPTION</STRONG>
This is a test for showing how to use the <STRONG><A HREF="../man1/nroff.1.html">nroff(1)</A></STRONG> man package.
It shows how to use .TH, .SH, .PP, .B, .I, and .IP commands.
This will be a new paragraph. You can also use normal <STRONG><A HREF="../man1/nroff.1.html">nroff(1)</A></STRONG>
commands in the text.
<STRONG>Nroff</STRONG> <STRONG>Commands</STRONG>
'\"' This is the comment command.
nf No fill mode (the normal mode is fill mode where things
get justified right and left).
fi Re-enter fill mode.
br Break line here no matter what.
sp Vertical space (also causes a break to occur).
Note that to continue an indent and make a new paragraph
(as is the case here), just put in a space (.sp).
Now we should be at a new paragraph.
</PRE>
<H2>CONVENTIONS</H2><PRE>
A typical manual page for a command or function is laid out as follows:
.TH TITLE [1-8]
The name of the command or function in upper-case,
which serves as the title of the manual page. This is
followed by the number of the section in which it
appears.
.SH NAME
name - one-line summary
The name, or list of names, by which the command is
called, followed by a dash and then a one-line summary
of the action performed. All in roman font, this sec-
tion contains no <STRONG><A HREF="../man1/troff.1.html">troff(1)</A></STRONG> commands or escapes, and no
macro requests. It is used to generate the <STRONG><A HREF="../man1/whatis.1.html">whatis(1)</A></STRONG>
database.
.SH SYNOPSIS
Commands:
The syntax of the command and its arguments as
typed on the command line. When in boldface, a
word must be typed exactly as printed. When in
italics, a word can be replaced with text that you
supply. Syntactic symbols appear in roman face:
[ ] An argument, when surrounded by brackets is
optional.
| Arguments separated by a vertical bar are
exclusive. You can supply only item from
such a list.
... Arguments followed by an elipsis can be
repeated. When an elipsis follows a brack-
eted set, the expression within the brackets
can be repeated.
Functions:
If required, the data declaration, or #include
directive, is shown first, followed by the func-
tion declaration. Otherwise, the function declara-
tion is shown.
.SH DESCRIPTION
A narrative description of the command or function in
detail, including how it interacts with files or data,
and how it handles the standard input, standard output
and standard error.
Filenames, and references to commands or functions
described elswhere in the manual, are italicised. The
names of options, variables and other literal terms are
in boldface.
.SH OPTIONS
The list of options along with a description of how
each affects the commands operation.
.SH ENVIRONMENT
Environment variables used.
.SH FILES
A list of files associated with the command or func-
tion.
.SH "SEE ALSO"
A comma-separated list of related manual pages,
followed by references to other published materials.
This section contains no <STRONG><A HREF="../man1/troff.1.html">troff(1)</A></STRONG> escapes or commands,
and no macro requests.
.SH DIAGNOSTICS
A list of diagnostic messages and an explanation of
each.
.SH NOTES
Any additional notes such as installation-dependent
functionality.
.SH BUGS
A description of limitations, known defects, and possi-
ble problems associated with the command or function.
.SH AUTHOR
The program's author and any pertinent release info.
.SH VERSION
The program's current version number and release date.
</PRE>
<H2>BUGS</H2><PRE>
Even though <STRONG><A HREF="../man1/cawf.1.html">cawf(1)</A></STRONG> has a better chance at formatting a random manual
page then the standard Minix nroff, it has two annoying bugs in its macro
set. Both .PP and .IP reset the indentation level to the level set by
.SH. This means that you can't use them in a piece of text indented by
.RS. For .IP this is troublesome, you can see why in the unformatted
source of this text. .PP can simply be replaced by .sp, or better yet,
by .SP with the following macro defined somewhere in your text:
.de SP
.if t .sp 0.4
.if n .sp
..
This will make .SP use 4/10 of a line if formatted by troff, just like
.PP.
</PRE>
</BODY>
</HTML>