commit 6227d0be31fc6e287feb44c82fbac15afd2bed71
parent 01455da77e4ef8619ef5fe558bbadca1e8049b69
Author: tjg <tjg>
Date: Thu, 25 Oct 2001 09:33:31 +0000
minor tidy ups
Diffstat:
| M | rc.1 | | | 90 | +++++++++++++++++++++++++++++++++++++++++++++++-------------------------------- |
1 file changed, 54 insertions(+), 36 deletions(-)
diff --git a/rc.1 b/rc.1
@@ -254,7 +254,8 @@ flag is present, or if the input to
.I rc
is not from a terminal, then
.I rc
-will not be in interactive mode. No prompts will be printed, and
+will not be in interactive mode.
+No prompts will be printed, and
.Cr SIGINT
will cause
.I rc
@@ -312,8 +313,8 @@ scripts; the usual caveats about the setuid bit still apply.)
.Cr \-s
This flag causes
.I rc
-to read from standard input. Any arguments are
-placed in
+to read from standard input.
+Any arguments are placed in
.Cr $* .
.TP
.Cr \-v
@@ -495,12 +496,14 @@ to the same file, use
.PP
As in
.IR sh ,
-redirections are processed from left to right. Thus this sequence
+redirections are processed from left to right.
+Thus this sequence
.Ds
.Cr "command >[2=1] > file"
.De
.PP
-is usually a mistake. It first duplicates standard error to standard
+is usually a mistake.
+It first duplicates standard error to standard
output; then redirects standard output to a file, leaving standard error
wherever standard output originally was.
.PP
@@ -629,7 +632,8 @@ redirection is implemented with some kind of pipe, and since one cannot
.IR lseek (2)
on a pipe, commands that use
.IR lseek (2)
-will hang. For example, some versions of
+will hang.
+For example, some versions of
.IR diff (1)
use
.IR lseek (2)
@@ -908,8 +912,9 @@ Note that the null string,
.Cr "''" ,
and the null list,
.Cr "()" ,
-are two very different things. Assigning the null string to a
-variable is a valid operation, but it does not remove its definition.
+are two very different things.
+Assigning the null string to a variable is a valid operation, but it
+does not remove its definition.
.Ds
.Cr "null = '' empty = () echo $#null $#empty"
.De
@@ -995,7 +1000,8 @@ has no
builtin.
.PP
Any non-empty sequence of characters, except a sequence including only
-digits, may be used as a variable name. Any character except
+digits, may be used as a variable name.
+Any character except
.Cr =
may be used, but special characters must be quoted.
All user-defined variables are exported into the environment.
@@ -1009,7 +1015,8 @@ operator:
.PP
Any variable which has not been assigned a value returns the null list,
.Cr "()" ,
-when referenced. Multiple references are allowed:
+when referenced.
+Multiple references are allowed:
.Ds
.Cr "a = foo"
.Cr "b = a"
@@ -1072,9 +1079,10 @@ Variables may be subscripted with the notation
.PP
where
.I n
-is a list of integers (origin 1). The opening parenthesis must
-immediately follow the variable name. The list of subscripts need not
-be in order or even unique. Thus,
+is a list of integers (origin 1).
+The opening parenthesis must immediately follow the variable name.
+The list of subscripts need not be in order or even unique.
+Thus,
.Ds
.Cr "a=(one two three)"
.Cr "echo $a(3 3 3)"
@@ -1130,7 +1138,8 @@ operator:
.De
.PP
This is useful when the normal list concatenation rules need to be
-bypassed. For example, to append a single period at the end of
+bypassed.
+For example, to append a single period at the end of
.Cr $path ,
use:
.Ds
@@ -1194,8 +1203,8 @@ as its value.
.SH "SPECIAL VARIABLES"
Several variables are known to
.I rc
-and are treated specially. In the following list,
-``(read only)'' indicates that an attempt to set the
+and are treated specially.
+In the following list, ``(read only)'' indicates that an attempt to set the
variable will silently have no effect.
.TP
.Cr *
@@ -1249,7 +1258,8 @@ Note also that an assignment to
.Cr $cdpath
causes an automatic assignment to
.Cr $CDPATH ,
-and vice-versa. Only
+and vice-versa.
+Only
.Cr $CDPATH
is exported into the environment.
.TP
@@ -1361,15 +1371,17 @@ is about to print
.Cr "$prompt(1)" .
.TP
.Cr status " (read only)"
-The exit status of the last command. If the command exited with a
-numeric value, that number is the status. If the command died with a
-signal, the status is the name of that signal; if a core file was
-created, the string
+The exit status of the last command.
+If the command exited with a numeric value, that number is the status.
+If the command died with a signal, the status is the name of that signal;
+if a core file was created, the string
.Rc `` +core ''
-is appended. The value of
+is appended.
+The value of
.Cr $status
for a pipeline is a list, with one entry, as above, for each process
-in the pipeline. For example, the command
+in the pipeline.
+For example, the command
.Ds
.Cr "ls | wc"
.De
@@ -1721,11 +1733,13 @@ is printed; for functions, including signal handlers, their definitions
are printed; for executable files, path names are printed; and for
variables, their values are printed.
The flags restrict output to builtins, functions, executable
-programs, signal handlers, and variables, respectively. If no
+programs, signal handlers, and variables, respectively.
+If no
.IR name s
are specified,
.I rc
-lists all objects of that type. (This is not permitted for
+lists all objects of that type.
+(This is not permitted for
.Cr \-p .)
Without arguments,
.Cr whatis
@@ -1821,7 +1835,8 @@ prints (with no final newline)
.SH "EXIT STATUS"
The exit status of
.I rc
-is normally the same as that of the last command executed. If the
+is normally the same as that of the last command executed.
+If the
last command was a pipeline,
.I rc
exits
@@ -1956,19 +1971,20 @@ On modern systems that support
or
.Cr /proc/self/fd ,
.Cr <{foo}
-style redirection is implemented that way. However, on older systems
-it is implemented with named pipes. Allegedly, it is sometimes
-possible to foil
+style redirection is implemented that way.
+However, on older systems it is implemented with named pipes.
+Allegedly, it is sometimes possible to foil
.I rc
into removing the FIFO it places in
.Cr /tmp
prematurely, or it is even possible to cause
.I rc
-to hang. (The current maintainer has never seen this, but then he
+to hang.
+(The current maintainer has never seen this, but then he
doesn't use systems which lack
.Cr /dev/fd
-any more. If anybody can reproduce this problem, please let the
-maintainer know.)
+any more.
+If anybody can reproduce this problem, please let the maintainer know.)
.PP
.B echo
is built in only for performance reasons, which is a bad idea.
@@ -1979,7 +1995,8 @@ Extra parentheses around a
.Cr ~
expression or a
.Cr !
-expression are a syntax error. Thus, this code is illegal.
+expression are a syntax error.
+Thus, this code is illegal.
.Ds
.Cr "while ((~ $1 -*) && (! ~ $1 --)) { ..."
.De
@@ -1997,7 +2014,8 @@ The Tenth Edition
.I rc
does not have the
.B else
-keyword. Instead,
+keyword.
+Instead,
.B if
is optionally followed by
an
@@ -2014,7 +2032,7 @@ This restriction is not present for single-word commands in this
.IR rc .
.PP
For
-.Cr .
+.Cr .
.IR file ,
the Tenth Edition
.IR rc
@@ -2029,7 +2047,7 @@ does not, since it is not considered useful.
The list flattening operator,
.Cr $^foo ,
is spelt
-.Cr "$\"foo"
+.Cr "$""foo"
in those versions of the Bell Labs
.IR rc
which have it.
