+.b
+$(\fIlist\fR)
+.e
+Either of these may be included in a word.
+During the command substitution process, the command (syntactly a
+.IR list )
+will be executed and anything that the command writes to the standard
+output will be captured by the shell. The final newline (if any) of
+the output will be deleted; the rest of the output will be substituted
+for the command in the word.
+.h "Word Splitting"
+When the value of a variable or the output of a command is substituted,
+the resulting text is subject to word splitting, unless the dollar sign
+introducing the variable or backquotes containing the text were enclosed
+in double quotes. In addition, ``$@'' is subject to a special type of
+splitting, even in the presence of double quotes.
+.PP
+Ash uses two different splitting algorithms. The normal approach, which
+is intended for splitting text separated by which space, is used if the
+first character of the shell variable IFS is a space. Otherwise an alternative
+experimental algorithm, which is useful for splitting (possibly empty)
+fields separated by a separator character, is used.
+.PP
+When performing splitting, the shell scans the replacement text looking
+for a character (when IFS does not begin with a space) or a sequence of
+characters (when IFS does begin with a space), deletes the character or
+sequence of characters, and spits the word into two strings at that
+point. When IFS begins with a space, the shell deletes either of the
+strings if they are null. As a special case, if the word containing
+the replacement text is the null string, the word is deleted.
+.PP
+The variable ``$@'' is special in two ways. First, splitting takes
+place between the positional parameters, even if the text is enclosed
+in double quotes. Second, if the word containing the replacement
+text is the null string and there are no positional parameters, then
+the word is deleted. The result of these rules is that "$@" is
+equivalent to "$1" "$2" ... "$\fIn\fR", where \fIn\fR is the number of
+positional parameters. (Note that this differs from the System V shell.
+The System V documentation claims that "$@" behaves this way; in fact
+on the System V shell "$@" is equivalent to "" when there are no
+positional paramteters.)
+.h "File Name Generation"
+Unless the
+.B -f
+flag is set, file name generation is performed after word splitting is
+complete. Each word is viewed as a series of patterns, separated by
+slashes. The process of expansion replaces the word with the names of
+all existing files whose names can be formed by replacing each pattern
+with a string that matches the specified pattern. There are two
+restrictions on this: first, a pattern cannot match a string containing
+a slash, and second, a pattern cannot match a string starting with a
+period unless the first character of the pattern is a period.
+.PP
+If a word fails to match any files and the
+.B -z
+flag is not set, then the word will be left unchanged (except that the
+meta-characters will be converted to normal characters). If the
+.B -z
+flag is set, then the word is only left unchanged if none
+of the patterns contain a character that can match anything besides
+itself. Otherwise the
+.B -z
+flag forces the word to be replaced with the names of the files that it
+matches, even if there are zero names.
+.h "Patterns"
+A
+.I pattern
+consists of normal characters, which match themselves, and meta-characters.
+The meta-characters are ``!'', ``*'', ``?'', and ``[''. These characters lose
+there special meanings if they are quoted. When command or variable
+substitution is performed and the dollar sign or back quotes are not
+double quoted, the value of the variable or the output of the command
+is scanned for these characters and they are turned into meta-characters.
+.PP
+Two exclamation points at the beginning of a pattern function as a ``not''
+operator, causing the pattern to match any string that the remainder of
+the pattern does
+.I not
+match. Other occurances of exclamation points in a pattern match
+exclamation points. Two exclamation points are required rather than one
+to decrease the incompatibility with the System V shell (which does not
+treat exclamation points specially).
+.PP
+An asterisk (``*'') matches any string of characters.
+A question mark matches any single character.
+A left bracket (``['') introduces a character class. The end of the
+character class is indicated by a ``]''; if the ``]'' is missing then
+the ``['' matches a ``['' rather than introducing a character class.
+A character class matches any of the characters between the square
+brackets. A range of characters may be specified using a minus sign.
+The character class may be complemented by making an exclamation point
+the first character of the character class.
+.PP
+To include a ``]'' in a character class, make it the first character listed
+(after the ``!'', if any).
+To include a minus sign, make it the first or last character listed.
+.h "The /u Directory"
+By convention, the name ``/u/user'' refers to the home directory of the
+specified user. There are good reasons why this feature should be supported
+by the file system (using a feature such as symbolic links) rather than
+by the shell, but
+.I ash
+is capable of performing this mapping if the file system doesn't.
+If the mapping is done by
+.IR ash ,
+setting the
+.B -f
+flag will turn it off.
+.h "Character Set"
+.I Ash
+silently discards nul characters. Any other character will be handled
+correctly by
+.IR ash ,
+including characters with the high order bit set.
+.h "Job Names and Job Control"
+The term
+.I job
+refers to a process created by a shell command, or in the case of a
+pipeline, to the set of processes in the pipeline. The ways to refer
+to a job are:
+.b
+%\fInumber\fR
+%\fIstring\fR
+%%
+\fIprocess_id\fR
+.e
+The first form identifies a job by job number.
+When a command is run,
+.I ash
+assigns it a job number
+(the lowest unused number is assigned).
+The second form identifies a job by giving a prefix of the command used
+to create the job. The prefix must be unique. If there is only one job,
+then the null prefix will identify the job, so you can refer to the job
+by writing ``%''. The third form refers to the \fIcurrent job\fR. The
+current job is the last job to be stopped while it was in the foreground.
+(See the next paragraph.) The last form identifies a job by giving the
+process id of the last process in the job.
+.PP
+If the operating system that
+.I ash
+is running on supports job control,
+.I ash
+will allow you to use it.
+In this case, typing the suspend character (typically ^Z) while running
+a command will return you to
+.I ash
+and will make the suspended command the current job. You can then continue
+the job in the background by typing
+.IR bg ,
+or you can continue it in the foreground by typing
+.IR fg .
+.h "Atty"
+If the shell variable ATTY is set, and the shell variable TERM is not
+set to ``emacs'', then \fIash\fR generates appropriate escape sequences
+to talk to
+.IR atty (1).
+.h "Exit Statuses"
+By tradition, an exit status of zero means that a command has succeeded
+and a nonzero exit status indicates that the command failed. This is
+better than no convention at all, but in practice it is extremely useful
+to allow commands that succeed to use the exit status to return information
+to the caller. A variety of better conventions have been proposed, but
+none of them has met with universal approval. The convention used by
+\fIash\fR and all the programs included in the \fIash\fR distribution is
+as follows:
+.ta 1i,2i
+.nf
+ 0 Success.
+ 1 Alternate success.
+ 2 Failure.
+ 129-... Command terminated by a signal.
+.fi
+The \fIalternate success\fR return is used by commands to indicate various
+conditions which are not errors but which can, with a little imagination,
+be conceived of as less successful than plain success. For example,
+.I test
+returns 1 when the tested condition is false and
+.I getopts
+returns 1 when there are no more options.
+Because this convention is not used universally, the
+.B -e
+option of
+.I ash
+causes the shell to exit when a command returns 1 even though that
+contradicts the convention described here.
+.PP
+When a command is terminated by a signal, the uses 128 plus the signal
+number as the exit code for the command.
+.h "Builtin Commands"
+This concluding section lists the builtin commands which are builtin
+because they need to perform some operation that can't be performed by a
+separate process. In addition to these, there are several other commands
+.RI ( catf ,
+.IR echo ,
+.IR expr ,
+.IR line ,
+.IR nlecho ,
+.IR test ,
+.RI `` : '',
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