56 lines
		
	
	
	
		
			703 B
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
	
		
			703 B
		
	
	
	
		
			Text
		
	
	
	
	
	
minus=-
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# standard input
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fd=0
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exec 3<&$fd
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read line <&3
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echo from stdin: $line
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# close fd 3
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exec 3<&${minus}
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# should give `bad fd', but exact error messages vary
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# read line <&3
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# standard output
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fd=1
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exec 4>&$fd
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echo to stdout >&4
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exec 4>&$minus
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# should give `bad fd', but exact error messages vary
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# echo to stdout >&4
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unset fd
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# these are ambiguous redirects
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exec 3<&$fd
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exec 4>&$fd
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exec 3>&1 4>&2
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exec >&/tmp/err-and-out
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echo to stdout
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echo to stderr >&2
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exec 1>&3 2>&4
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echo /tmp/err-and-out:
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cat /tmp/err-and-out
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rm /tmp/err-and-out
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fd=/tmp/err-and-out
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exec >&$fd
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echo to stdout
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echo to stderr >&2
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exec 1>&3 2>&4
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echo /tmp/err-and-out:
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cat /tmp/err-and-out
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rm /tmp/err-and-out
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