diff options
author | Paul Eggert <eggert@cs.ucla.edu> | 2004-09-09 00:29:09 +0000 |
---|---|---|
committer | Paul Eggert <eggert@cs.ucla.edu> | 2004-09-09 00:29:09 +0000 |
commit | 88fde700e1097120f01858b350862eb80a19b4e0 (patch) | |
tree | d280fbf50048629d7ac60e665b064546d2e9b4e7 | |
parent | 66942e36a8b988edc2b7f7284e694de2768c4ef8 (diff) | |
download | coreutils-88fde700e1097120f01858b350862eb80a19b4e0.tar.xz |
(Common options): Some programs don't reorder
options.
(tr invocation, echo invocation, printf invocation, test invocation,
expr invocation, basename invocation, chroot invocation,
nice invocation, nohup invocation, seq invocation):
This program doesn't reorder options.
(tr invocation): Mention --help, --version, --.
(echo invocation): Mention that -- isn't special.
(test invocation): Mention that the expression is optional,
and that test ! EXPR is like ! test EXPR.
(expr invocation): Mention --help, --version.
-rw-r--r-- | doc/coreutils.texi | 44 |
1 files changed, 39 insertions, 5 deletions
diff --git a/doc/coreutils.texi b/doc/coreutils.texi index a71a3fe39..b1e6abbcb 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -600,6 +600,13 @@ as if all the options appear before any operands. For example, @env{POSIXLY_CORRECT} environment variable is set, options must appear before operands, unless otherwise specified for a particular command. +A few programs can usefully have trailing operands with leading +@samp{-}. With such a program, options must precede operands even if +@env{POSIXLY_CORRECT} is not set, and this fact is noted in the +program description. For example, the @command{env} command's options +must appear before its operands, since in some cases the operands +specify a command that itself contains options. + Some of these programs recognize the @option{--help} and @option{--version} options only when one of them is the sole command line argument. @@ -4749,6 +4756,9 @@ This distinction will matter only when some values are not characters, and this is possible only in locales using multibyte encodings when the input contains encoding errors. +The program accepts the @option{--help} and @option{--version} +options. @xref{Common options}. Options must precede operands. + @exitstatus @menu @@ -5060,6 +5070,12 @@ of characters: tr -d axM- @end example +Or you can use @samp{--} to terminate option processing: + +@example +tr -d -- -axM +@end example + More generally, use the character class notation @code{[=c=]} with @samp{-} (or any other character) in place of the @samp{c}: @@ -9052,6 +9068,9 @@ echo [@var{option}]@dots{} [@var{string}]@dots{} @end example The program accepts the following options. Also see @ref{Common options}. +Options must precede operands, and the normally-special argument +@samp{--} has no special meaning and is treated like any other +@var{string}. @table @samp @item -n @@ -9217,6 +9236,7 @@ use of @samp{\u} and @samp{\U} will give an error message. The only options are a lone @option{--help} or @option{--version}. @xref{Common options}. +Options must precede operands. The Unicode character syntaxes are useful for writing strings in a locale independent way. For example, a string containing the Euro currency symbol @@ -9378,14 +9398,22 @@ not have the desired effect. Since @samp{test @var{expr}} and @samp{[ @var{expr} ]} have the same meaning, only the former form is discussed below. +Synopses: + +@example +test [@var{expression}] +[ [@var{expression}] ] +@end example + @cindex conflicts with shell built-ins @cindex built-in shell commands, conflicts with Because most shells have a built-in command by the same name, using the unadorned command name in a script or interactively may get you different functionality than that described here. -Besides the options below, a single argument is also allowed: -@command{test} returns true if the argument is not null. The argument +If @var{expression} is omitted, @command{test} returns false. +If @var{expression} is a single argument, +@command{test} returns false if the argument is null and true otherwise. The argument can be any string, including strings like @samp{-d}, @samp{-1}, @samp{--}, @samp{--help}, and @samp{--version} that most other programs would treat as options. To get help and version information, @@ -9712,6 +9740,9 @@ may be used for grouping in the usual manner. You must quote parentheses and many operators to avoid the shell evaluating them, however. +The only options are @option{--help} and @option{--version}. @xref{Common +options}. Options must precede operands. + @cindex exit status of @command{expr} Exit status: @@ -10028,7 +10059,7 @@ it is removed from @var{name} as well. @command{basename} prints the result on standard output. The only options are @option{--help} and @option{--version}. @xref{Common -options}. +options}. Options must precede operands. @exitstatus @@ -11961,7 +11992,7 @@ specified, the default is the value of the @env{SHELL} environment variable or @command{/bin/sh} if not set, invoked with the @option{-i} option. The only options are @option{--help} and @option{--version}. @xref{Common -options}. +options}. Options must precede operands. Here are a few tips to help avoid common problems in using chroot. To start with a simple example, make @var{command} refer to a statically @@ -12035,6 +12066,7 @@ specifications, the resulting environment is printed. This is like specifying a command name of @command{printenv}. The program accepts the following options. Also see @ref{Common options}. +Options must precede operands. @table @samp @@ -12104,6 +12136,7 @@ unadorned command name in a script or interactively may get you different functionality than that described here. The program accepts the following option. Also see @ref{Common options}. +Options must precede operands. @table @samp @item -n @var{adjustment} @@ -12222,7 +12255,7 @@ scheduling priority of @var{command}; use @command{nice} for that, e.g., @samp{nohup nice @var{command}}. The only options are @option{--help} and @option{--version}. @xref{Common -options}. +options}. Options must precede operands. @cindex exit status of @command{nohup} Exit status: @@ -12691,6 +12724,7 @@ Floating-point numbers may be specified (using a period before any fractional digits). The program accepts the following options. Also see @ref{Common options}. +Options must precede operands. @table @samp @item -f @var{format} |