INTRO(1)

NAME
intro - introduction to commands

DESCRIPTION
The Heirloom Toolchest is a collection of standard Unix utilities that is intended to provide maximum compatibility with traditional Unix while incorporating additional features necessary today. To achieve this, utilities are derived from original Unix sources if permitted by its licenses. This means that material from Unix 6th Edition, Unix 7th Edition, and Unix 32V was used, since these systems were put under an Open Source license by Caldera in January 2002. In addition, 4BSD source (governed by the University's copyright and partially derived from 32V) has been used. (Other sources were Sun's `OpenSolaris', Caldera's `Open Source Unix[tm] Tools', the MINIX utility collection, Plan 9, and Info-ZIP's compression codes.) If no freely available Unix sources were available (for example, for tools introduced in System III or System V), utilities were rewritten from scratch. (The exact license terms are provided in a separate document.)

The tools in this collection are oriented on the specifications or systems named below. Since there are some incompatibilities between them, some tools are present in more than one version.

–   System V Interface Definition, Third Edition (UNIX System Laboratories, 1992) (SVID3). This specification corresponds to a System V Release 4 or Solaris 2 system. Utilities in /usr/5bin are modeled after this specification and related system environments. If extensions introduced in POSIX.2 or POSIX.1-2001 (see below) did not provoke conflicts with the behavior at this level, they were incorporated in these utilities as well. This is the most traditional personality available with the Heirloom Toolchest; prominently, regular expressions do not have any of the internationalization features (see ed(1) and egrep(1)), and awk is the old version, oawk(1). Use this personality to get best compatibility with traditional System V behavior.

–   System V Interface Definition, Fourth Edition (Novell, Inc., 1995) (SVID4). This specification corresponds to a System V Release 4.2 MP system. Utilities in /usr/5bin/s42 are modeled after this specification and related system environments. If extensions introduced in POSIX.2 or POSIX.1-2001 (see below) did not provoke conflicts with the behavior at this level, they were incorporated in these utilities as well. The most essential difference between this and the SVID3 personality are internationalized regular expressions and the choice of the new awk, nawk(1), for awk. Use this personality to get traditional System V behavior combined with internationalized regular expressions.

–   ISO/IEC 9945-2:1993 / ANSI/IEEE Std 1003.2-1992 (POSIX.2), with the extensions of The Single UNIX Specification, Version 2 (The Open Group, 1997). Utilities in /usr/5bin/posix are intended to fully comply to this specification even in cases of conflict with historical behavior. Non-conflicting extensions to POSIX.2 found in the environments described above are also present in these utilities. Use this personality if you need POSIX.2 features in preference to traditional System V ones.

–   ISO/IEC 9945-1:2001 / ANSI/IEEE Std 1003.1-2001 (POSIX.1-2001), with the extensions of The Single UNIX Specification, Version 3 (The Open Group, 2001). Utilities in /usr/5bin/posix2001 are intended to fully comply to this specification even in cases of conflict with historical behavior. Non-conflicting extensions to POSIX.1-2001 found in the environments described above are also present in these utilities. Use this personality if you need POSIX.1-2001 features in preference to traditional System V ones.

To use the Heirloom Toolchest, select one of these personalities and put the corresponding directory at the beginning of the PATH environment variable, immediately followed by the toolchest base directory, @.DEFBIN.@ (which contains the tools that are the same for all personalities). For example, to use the toolchest with a SVID4 personality, execute

    PATH=/usr/5bin/s42:@.DEFBIN.@:$PATH export PATH

You must select exactly one of the personalities above; you do not have access to the complete set of tools otherwise.

The manual pages generally note which behavior corresponds to which utility version. They also mark whether options and arguments were part of System V, were introduced with POSIX.2 or POSIX.1-2001, or if they are extensions provided by the Heirloom Toolchest, (possibly oriented at extensions introduced by other vendors). Such extensions are subject to change without a grace period; they are only intended for interactive usage and should not be included in scripts.

The toolchest also includes some utilities modeled after the BSD Compatibility environment of System V; these roughly correspond to 4.3BSD or SunOS 4 systems. These tools can be found in /usr/ucb; since they do not form a full personality set as the ones described above, they should be used in addition, as e.g.

    PATH=/usr/ucb:/usr/5bin/s42:@.DEFBIN.@:$PATH export PATH

does.

While the Heirloom Toolchest is intended to be as compatible as possible with historical practice in general, annoying static limits of historical implementations are not present any longer. Input lines of unlimited length are generally accepted (as long as enough memory is available); most utilities are also able to handle binary input data (i.e. ASCII NUL characters in the input stream).

  Multibyte character encodings
The Heirloom Toolchest includes support for multibyte character encodings; if the underlying C library supports this and the LC_CTYPE locale (see locale(7) for an introduction) is set appropriately, multiple input bytes can form a single character and are handled as such in regular expressions, display width computations etc.

Multibyte character support was designed with special regard to the UTF-8 encoding. Additional supported encodings are EUC-JP, EUC-KR, Big5, Big5-HKSCS, GB 2312, and GBK. Other encodings may also work, with the following restrictions:

–   The character set must be a superset of ASCII (more specifically, of the International Reference Version of ISO 646). All ASCII characters must be encoded as a single byte with the same value as the ASCII character. This excludes 7-bit encodings like UTF-7. In addition, the C language implementation must map each ASCII character to a wide character with the same value.

–   The first byte of each multibyte character must have the highest bit set, i.e. it must not be an ASCII character. This excludes encodings whose sequences start with ASCII characters like TCVN 5712.

–   Locking-shift encodings, like those that use ISO 2022 escape sequences, are not supported.

Character comparison, regular expression matching and similar tasks are generally performed on the character representation obtained from the locale processing of the C library. A glyph formed by the application of combining characters to a base character will thus not normally be considered equal to the same glyph represented by a single base character. For string comparison, the results depend on the collation mechanism of the locale, which might or might not respect such relations.

Processing of multibyte character encodings is often notably slower than that of singlebyte character encodings. Since many widely-used languages (especially European ones based on Latin letters) contain few multibyte characters if encoded in UTF-8, and since experience shows that large amounts of textual data tend to be machine generated and to contain mostly ASCII characters (e.g. log files), while international language texts are mostly created by humans and tend to be smaller, processing of text in multibyte locales has generally been optimized for ASCII text. The performance penalty for using a multibyte locale is thus usually low if no or few multibyte characters actually occur in the data processed.

A problem with multibyte encodings that does not normally occur in singlebyte encodings is that of illegal byte sequences. In a singlebyte locale, each byte is treated as a character entity even if its value is not defined in the coded character set. For example, bytes with their highest bit set are simply passed through in the default `C' or `POSIX' locale, and can appear in option arguments as well as in input data. In multibyte locales however, byte sequences that do not form a valid character cannot be handled this way, because it is not always clear which bytes are to be grouped together. As an example, suppose that the `\200' byte introduces a multibyte sequence. If this byte occurs in a string to be matched by a utility but is not followed by a valid continuation byte, it is unclear if it should match any byte sequence containing this byte, including valid ones that form a character, or if matches should be restricted to occurences in other incomplete sequences. For this reason, this implementation generally treats illegal byte sequences in command line arguments or programming scripts as syntax errors. Utilities do not issue a warning or even terminate with an error if such sequences appear in input data, though, since this frequently occurs in practice when processing binary or foreign-locale files. In most cases, the sequences are passed to the output unaltered. That data is accepted or generated by a utility can thus not be taken as an indication for its validity in respect to the current character encoding.

  List of commands
Name | Appears on Page | Description
apropos | apropos(1) | locate commands by keyword lookup
banner | banner(1) | make posters
basename | basename(1) | return non-directory portion of a pathname
basename | basename(1B) | (BSD) return non-directory portion of a pathname
bc | bc(1) | arbitrary-precision arithmetic language
bdiff | bdiff(1) | big diff
bfs | bfs(1) | big file scanner
cal | cal(1) | print calendar
calendar | calendar(1) | reminder service
cat | cat(1) | concatenate and print files
catman | catman(8) | create the formatted files for the reference manual
chgrp | chown(1) | change owner or group
chmod | chmod(1) | change mode
chown | chown(1) | change owner or group
chown | chown(1B) | (BSD) change file ownwer
cksum | cksum(1) | write file checksums and sizes
cmp | cmp(1) | compare two files
col | col(1) | filter reverse line feeds
comm | comm(1) | select or reject lines common to two sorted files
copy | copy(1XNX) | (XENIX) copy groups of files
cp | cp(1) | copy files
cpio | cpio(1) | copy file archives in and out
csplit | csplit(1) | context split
cut | cut(1) | cut out selected fields of each line of a file
date | date(1) | print or set the date
dc | dc(1) | desk calculator
dd | dd(1) | convert and copy a file
deroff | deroff(1) | remove nroff/troff, tbl, and eqn constructs
deroff | deroff(1B) | (BSD) remove nroff, troff, tbl and eqn constructs
df | df(1) | disk free
df | df(1B) | (BSD) disk free
dfspace | df(1) | disk free
diff | diff(1) | differential file comparator
diff3 | diff3(1) | 3-way differential file comparison
dircmp | dircmp(1) | directory comparison
dirname | dirname(1) | return the directory portion of a pathname
du | du(1) | summarize disk usage
du | du(1B) | (BSD) summarize disk usage
echo | echo(1) | echo arguments
echo | echo(1B) | (BSD) echo arguments
ed | ed(1) | text editor
egrep | egrep(1) | search a file for a pattern using full regular expressions
env | env(1) | set environment for command invocation
expand | expand(1) | convert tabs to spaces
expr | expr(1) | evaluate arguments as an expression
factor | factor(1) | factor a number
false | true(1) | provide truth values
fgrep | fgrep(1) | search a file for a character string
file | file(1) | determine file type
find | find(1) | find files
fmt | fmt(1) | simple text formatter
fmtmsg | fmtmsg(1) | display a message in standard format
fold | fold(1) | fold long lines
getconf | getconf(1) | get configuration values
getopt | getopt(1) | parse command options
grep | grep(1) | search a file for a pattern
groups | groups(1) | show group memberships
groups | groups(1B) | (BSD) show group memberships
hd | hd(1XNX) | (XENIX) display files in hexadecimal format
head | head(1) | display first few lines of files
hostname | hostname(1) | set or print name of current host system
id | id(1) | print user and group IDs and names
install | install(1B) | (BSD) install files
join | join(1) | relational database operator
kill | kill(1) | terminate a process
lc | ls(1) | list contents of directory
line | line(1) | read one line
listusers | listusers(1) | print a list of user logins
ln | ln(1) | make a link
ln | ln(1B) | (BSD) make links
logins | logins(1) | list login information
logname | logname(1) | get login name
ls | ls(1) | list contents of directory
ls | ls(1B) | (BSD) list contents of directory
mail | mail(1) | send or receive mail among users
man | man(1) | find and display reference manual pages
mesg | mesg(1) | permit or deny messages
mkdir | mkdir(1) | make a directory
mkfifo | mkfifo(1) | make FIFO special file
mknod | mknod(1M) | build special file
more | more(1) | browse or page through a text file
mt | mt(1) | magnetic tape utility
mv | mv(1) | move or rename files and directories
mvdir | mvdir(1) | move a directory
nawk | nawk(1) | pattern scanning and processing language
newform | newform(1) | change the format of a text file
news | news(1) | print news items
nice | nice(1) | run a command at low priority
nl | nl(1) | line numbering filter
nohup | nohup(1) | run a command immune to hangups
oawk | oawk(1) | pattern scanning and processing language
od | od(1) | octal dump
page | more(1) | browse or page through a text file
paste | paste(1) | merge same lines of several files or subsequent lines of one file
pathchk | pathchk(1) | check pathnames
pax | pax(1) | portable archive interchange
pg | pg(1) | file perusal filter for CRTs
pgrep | pgrep(1) | find or signal processes by name and other attributes
pkill | pgrep(1) | find or signal processes by name and other attributes
pr | pr(1) | print files
printenv | printenv(1) | print out the environment
printf | printf(1) | print a text string
priocntl | priocntl(1) | process scheduler control
ps | ps(1) | process status
ps | ps(1B) | (BSD) process status
psrinfo | psrinfo(1) | displays information about processors
ptime | time(1) | time a command
pwd | pwd(1) | working directory name
random | random(1XNX) | (XENIX) generate a random number
renice | renice(1) | alter priority of running processes
rm | rm(1) | remove directory entries
rmdir | rmdir(1) | remove directories
sdiff | sdiff(1) | print file differences side-by-side
sed | sed(1) | stream editor
setpgrp | setpgrp(1) | set process group ID and session ID
settime | settime(1XNX) | (XENIX) change the access and modification dates of files
shl | shl(1) | shell layer manager
sleep | sleep(1) | suspend execution for an interval
sort | sort(1) | sort or merge files
spell | spell(1) | find spelling errors
split | split(1) | split a file into pieces
stty | stty(1) | set the options for a terminal
stty | stty(1B) | (BSD) set the options for a terminal
su | su(1) | become super-user or another user
sum | sum(1) | sum and count blocks in a file
sum | sum(1B) | (BSD) sum and count blocks in a file
sync | sync(1M) | update the super block
tabs | tabs(1) | set terminal tabs
tail | tail(1) | deliver the last part of a file
tape | tape(1) | magnetic tape maintenance
tapecntl | tapecntl(1) | tape control for tape devices
tar | tar(1) | tape archiver
tcopy | tcopy(1) | copy a magnetic tape
tee | tee(1) | pipe fitting
test | test(1) | condition command
test | test(1B) | (BSD) condition command
time | time(1) | time a command
touch | touch(1) | update file access and modification times
tr | tr(1) | translate characters
tr | tr(1B) | (BSD) translate characters
true | true(1) | provide truth values
tsort | tsort(1) | topological sort
tty | tty(1) | get terminal name
ul | ul(1) | underline
uname | uname(1) | get system name
unexpand | unexpand(1) | convert spaces to tabs
uniq | uniq(1) | report repeated lines in a file
units | units(1) | conversion program
uptime | uptime(1) | show how long system has been up
users | users(1) | display a compact list of users logged in
w | w(1) | who is on and what they are doing
wc | wc(1) | word count
what | what(1) | identify SCCS files
whatis | whatis(1) | display a one-line summary about a keyword
who | who(1) | who is on the system
whoami | whoami(1) | display the effective current username
whodo | whodo(1) | who is doing what
xargs | xargs(1) | construct argument list(s) and execute command
yes | yes(1XNX) | (XENIX) print strint repeatedly

  Other manual entries
Page | Description
fspec(5) | format specifications in text files
intro(1) | introduction to commands
man(7) | macros to typeset manual