shell_cmds-53.tar.gz

[apple/shell_cmds.git] / getopt / getopt.1

diff --git a/getopt/getopt.1 b/getopt/getopt.1
index 410f61b64dc311540689088e4816d5a3becd3cd9..793c87a68ca23a8f6065db33f376671caf9253de 100644 (file)
--- a/getopt/getopt.1
+++ b/getopt/getopt.1
@@ -1,69 +1,79 @@
-.\"    $NetBSD: getopt.1,v 1.8 1997/10/19 02:16:57 lukem Exp $
-.Dd June 21, 1993
+.\" $FreeBSD: src/usr.bin/getopt/getopt.1,v 1.15 2002/04/19 23:43:02 charnier Exp $
+.\"
+.Dd April 3, 1999

 .Dt GETOPT 1
 .Os
 .Sh NAME
 .Nm getopt
 .Nd parse command options
 .Sh SYNOPSIS
 .Dt GETOPT 1
 .Os
 .Sh NAME
 .Nm getopt
 .Nd parse command options
 .Sh SYNOPSIS

-.Li args=\`getopt optstring $*\`
-.Pp
-.Li set \-\- \`getopt optstring $*\`
+.Nm args=\`getopt Ar optstring $*\`
+; errcode=$?; set \-\- $args

 .Sh DESCRIPTION
 .Sh DESCRIPTION

+The

 .Nm
 .Nm

-is used to break up options in command lines for easy parsing by
+utility is used to break up options in command lines for easy parsing by

 shell procedures, and to check for legal options.
 shell procedures, and to check for legal options.

-.Op Optstring
+.Ar Optstring

 is a string of recognized option letters (see
 is a string of recognized option letters (see

-.Xr getopt 3
-);
+.Xr getopt 3 ) ;

 if a letter is followed by a colon, the option
 is expected to have an argument which may or may not be
 separated from it by white space.
 The special option
 if a letter is followed by a colon, the option
 is expected to have an argument which may or may not be
 separated from it by white space.
 The special option

-.Dq \-\-
+.Ql \-\-

 is used to delimit the end of the options.
 is used to delimit the end of the options.

+The

 .Nm
 .Nm

-will place
-.Dq \-\-
+utility will place
+.Ql \-\-

 in the arguments at the end of the options,
 or recognize it if used explicitly.
 The shell arguments
 (\fB$1 $2\fR ...) are reset so that each option is
 preceded by a
 in the arguments at the end of the options,
 or recognize it if used explicitly.
 The shell arguments
 (\fB$1 $2\fR ...) are reset so that each option is
 preceded by a

-.Dq \-
+.Ql \-

 and in its own shell argument;
 each option argument is also in its own shell argument.
 and in its own shell argument;
 each option argument is also in its own shell argument.

-.Sh EXAMPLE
+.Sh EXAMPLES

 The following code fragment shows how one might process the arguments
 for a command that can take the options
 The following code fragment shows how one might process the arguments
 for a command that can take the options

-.Op a
+.Fl a

 and
 and

-.Op b ,
+.Fl b ,

 and the option
 and the option

-.Op o ,
+.Fl o ,

 which requires an argument.
 .Pp
 .Bd -literal -offset indent
 args=\`getopt abo: $*\`
 which requires an argument.
 .Pp
 .Bd -literal -offset indent
 args=\`getopt abo: $*\`

-if test $? != 0
+# you should not use \`getopt abo: "$@"\` since that would parse
+# the arguments differently from what the set command below does.
+if [ $? != 0 ]

 then
        echo 'Usage: ...'
        exit 2
 fi
 set \-\- $args
 then
        echo 'Usage: ...'
        exit 2
 fi
 set \-\- $args

+# You cannot use the set command with a backquoted getopt directly,
+# since the exit code from getopt would be shadowed by those of set,
+# which is zero by definition.

 for i
 do
        case "$i"
        in
                \-a|\-b)
 for i
 do
        case "$i"
        in
                \-a|\-b)

-                       flag=$i; shift;;
+                       echo flag $i set; sflags="${i#-}$sflags";
+                       shift;;

                \-o)
                \-o)

-                       oarg=$2; shift; shift;;
+                       echo oarg is "'"$2"'"; oarg="$2"; shift;
+                       shift;;

                \-\-)
                        shift; break;;
        esac
 done
                \-\-)
                        shift; break;;
        esac
 done

+echo single-char flags: "'"$sflags"'"
+echo oarg is "'"$oarg"'"

 .Ed
 .Pp
 This code will accept any of the following as equivalent:
 .Ed
 .Pp
 This code will accept any of the following as equivalent:


@@ -73,49 +83,52 @@ cmd \-aoarg file file
 cmd \-a \-o arg file file
 cmd \-oarg -a file file
 cmd \-a \-oarg \-\- file file
 cmd \-a \-o arg file file
 cmd \-oarg -a file file
 cmd \-a \-oarg \-\- file file

-.Ed

 .Pp
 .Pp

-.St -p1003.2
-mandates that the 
-.Xr sh 1
-set command return the value of 0 for the exit status.  Therefore,
-the exit status of the
-.Nm
-command is lost when
-.Nm
-and the
-.Xr sh 1
-set command are used on the same line.  The example given
-is one way to detect errors found by 
-.Nm "" .
+.Ed

 .Sh SEE ALSO
 .Xr sh 1 ,
 .Xr getopt 3
 .Sh DIAGNOSTICS
 .Sh SEE ALSO
 .Xr sh 1 ,
 .Xr getopt 3
 .Sh DIAGNOSTICS

+The

 .Nm
 .Nm

-prints an error message on the standard error output when it
-encounters an option letter not included in
-.Op optstring .
+utility prints an error message on the standard error output and exits with
+status > 0 when it encounters an option letter not included in
+.Ar optstring .

 .Sh HISTORY
 .Sh HISTORY

-Written by Henry Spencer, working from a Bell Labs manual page.
+Written by
+.An Henry Spencer ,
+working from a Bell Labs manual page.

 Behavior believed identical to the Bell version.
 Behavior believed identical to the Bell version.

+Example changed in
+.Fx
+version 3.2 and 4.0.

 .Sh BUGS
 Whatever
 .Xr getopt 3
 has.
 .Pp
 Arguments containing white space or embedded shell metacharacters
 .Sh BUGS
 Whatever
 .Xr getopt 3
 has.
 .Pp
 Arguments containing white space or embedded shell metacharacters

-generally will not survive intact;  this looks easy to fix but isn't.
+generally will not survive intact;  this looks easy to fix but
+isn't. People trying to fix
+.Nm
+or the example in this manpage should check the history of this file
+in
+.Fx .

 .Pp
 The error message for an invalid option is identified as coming
 from
 .Nm
 rather than from the shell procedure containing the invocation
 of
 .Pp
 The error message for an invalid option is identified as coming
 from
 .Nm
 rather than from the shell procedure containing the invocation
 of

-.Nm "" ;
+.Nm ;

 this again is hard to fix.
 .Pp
 The precise best way to use the
 this again is hard to fix.
 .Pp
 The precise best way to use the

-.Ic set
+.Nm set

 command to set the arguments without disrupting the value(s) of
 shell options varies from one shell version to another.
 command to set the arguments without disrupting the value(s) of
 shell options varies from one shell version to another.

+.Pp
+Each shellscript has to carry complex code to parse arguments halfway
+correcty (like the example presented here). A better getopt-like tool
+would move much of the complexity into the tool and keep the client
+shell scripts simpler.