82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
		
			Executable File
		
	
	
	
	
| # Simple usage cases for getopts.
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| #
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| # OPTIND is either not touched at all (first loop with getopts,
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| # relying on shell startup init), or getopts state is reset
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| # before new loop with "unset OPTIND", "OPTIND=1" or "OPTIND=0".
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| #
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| # Each option is a separate argument (no "-abc"). This conceptually
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| # needs only $OPTIND to hold getopts state.
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| #
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| # We check that loop does not stop on unknown option (sets "?"),
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| # stops on _first_ non-option argument.
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| 
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| (
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| 
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| echo "*** no OPTIND, optstring:'ab' args:-a -b c"
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| var=QWERTY
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| while getopts "ab" var -a -b c; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| # unfortunately, "rc:0" is shown since while's overall exitcode is "success"
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # Resetting behavior =1
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| echo "*** OPTIND=1, optstring:'ab' args:-a -b c"
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| OPTIND=1
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| while getopts "ab" var -a -b c; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # Resetting behavior =0
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| echo "*** OPTIND=0, optstring:'ab' args:-a -b c"
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| OPTIND=0
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| while getopts "ab" var -a -b c; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # Resetting behavior "unset"
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| echo "*** unset OPTIND, optstring:'ab' args:-a -b c"
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| unset OPTIND
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| while getopts "ab" var -a -b c; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # What is the final exitcode?
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| echo "*** optstring:'ab' args:-a -b c"
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| unset OPTIND
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| getopts "ab" var -a -b c; echo "1 rc:$? var:'$var' OPTIND:$OPTIND"
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| getopts "ab" var -a -b c; echo "2 rc:$? var:'$var' OPTIND:$OPTIND"
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| getopts "ab" var -a -b c; echo "3 rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # Where would it stop? c or -c?
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| echo "*** unset OPTIND, optstring:'ab' args:-a c -c -b d"
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| unset OPTIND
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| while getopts "ab" var -a c -c -b d; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # What happens on unknown option?
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| echo "*** unset OPTIND, optstring:'ab' args:-a -c -b d"
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| unset OPTIND
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| while getopts "ab" var -a -c -b d; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| # ORTERR=0 suppresses error message?
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| echo "*** unset OPTIND, OPTERR=0, optstring:'ab' args:-a -c -b d"
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| unset OPTIND
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| OPTERR=0
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| while getopts "ab" var -a -c -b d; do
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| 	echo "var:'$var' OPTIND:$OPTIND"
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| done
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| echo "exited: rc:$? var:'$var' OPTIND:$OPTIND"
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| 
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| ) 2>&1 \
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| | sed	-e 's/ unrecognized option: / invalid option -- /' \
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| 	-e 's/ illegal option -- / invalid option -- /' \
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