📄 exec6.sub
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# builtins with exit status inverted( true )echo $?( ! true )echo $?( false )echo $?( ! false )echo $?# inverting shouldn't affect exit(exit 42)echo $?( ! exit 42 )echo $?# commands requiring an exec with exit status inverted -- broken in bash-2.04( ls > /dev/null 2>&1 )echo $?( ! ls > /dev/null 2>&1 )echo $?touch /tmp/notwritechmod 400 /tmp/notwrite# make sure redirection failures in commands whose exit status is inverted# are handled correctly( ls > /tmp/notwrite ) 2>/dev/nullecho $?( ! ls > /tmp/notwrite ) 2>/dev/nullecho $?# now add exit traps, true and false for commands with and without exit# status inversion(trap 'false' 0 ; ! ls > /tmp/notwrite ) 2>/dev/nullecho $?(trap 'false' 0 ; ls > /tmp/notwrite ) 2>/dev/nullecho $?(trap 'true' 0 ; ! ls > /tmp/notwrite ) 2>/dev/nullecho $?(trap 'true' 0 ; ls > /tmp/notwrite ) 2>/dev/nullecho $?rm -f /tmp/notwrite
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