| 1 | ## oils_failures_allowed: 5
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| 2 | ## compare_shells: bash mksh ash
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| 3 |
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| 4 | # Notes on bash semantics:
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| 5 | #
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| 6 | # https://www.gnu.org/software/bash/manual/bash.html
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| 7 | #
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| 8 | # The trap builtin (see Bourne Shell Builtins) allows an ERR pseudo-signal
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| 9 | # specification, similar to EXIT and DEBUG. Commands specified with an ERR trap
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| 10 | # are executed after a simple command fails, with a few exceptions. The ERR
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| 11 | # trap is not inherited by shell functions unless the -o errtrace option to the
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| 12 | # set builtin is enabled.
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| 13 |
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| 14 |
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| 15 | #### trap can use original $LINENO
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| 16 |
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| 17 | trap 'echo line=$LINENO' ERR
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| 18 |
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| 19 | false
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| 20 | false
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| 21 | echo ok
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| 22 |
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| 23 | ## STDOUT:
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| 24 | line=3
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| 25 | line=4
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| 26 | ok
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| 27 | ## END
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| 28 |
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| 29 | #### trap ERR and if statement
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| 30 |
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| 31 | if test -f /nope; then echo file exists; fi
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| 32 |
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| 33 | trap 'echo err' ERR
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| 34 | #trap 'echo line=$LINENO' ERR
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| 35 |
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| 36 | if test -f /nope; then echo file exists; fi
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| 37 |
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| 38 | ## STDOUT:
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| 39 | ## END
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| 40 |
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| 41 | #### trap ERR does not run in errexit situations
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| 42 |
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| 43 | trap 'echo line=$LINENO' ERR
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| 44 |
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| 45 | if false; then
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| 46 | echo if
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| 47 | fi
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| 48 |
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| 49 | while false; do
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| 50 | echo while
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| 51 | done
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| 52 |
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| 53 | until false; do
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| 54 | echo until
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| 55 | break
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| 56 | done
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| 57 |
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| 58 | false || false || false
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| 59 |
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| 60 | false && false && false
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| 61 |
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| 62 | false; false; false
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| 63 |
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| 64 | echo ok
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| 65 |
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| 66 | ## STDOUT:
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| 67 | until
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| 68 | line=16
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| 69 | line=20
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| 70 | line=20
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| 71 | line=20
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| 72 | ok
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| 73 | ## END
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| 74 |
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| 75 | #### trap ERR pipeline (also errexit)
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| 76 |
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| 77 | # mksh and bash have different line numbers in this case
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| 78 | #trap 'echo line=$LINENO' ERR
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| 79 | trap 'echo line=$LINENO' ERR
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| 80 |
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| 81 | # it's run for the last 'false'
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| 82 | false | false | false
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| 83 |
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| 84 | { echo pipeline; false; } | false | false
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| 85 |
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| 86 | # it's never run here
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| 87 | ! true
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| 88 | ! false
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| 89 |
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| 90 | ## STDOUT:
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| 91 | line=3
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| 92 | line=5
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| 93 | ## END
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| 94 |
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| 95 | ## BUG mksh/ash STDOUT:
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| 96 | line=1
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| 97 | line=1
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| 98 | ## END
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| 99 |
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| 100 | #### trap ERR subprogram - subshell, command sub, async
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| 101 |
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| 102 | trap 'echo line=$LINENO' ERR
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| 103 |
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| 104 | ( false; echo subshell )
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| 105 |
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| 106 | x=$( false; echo command sub )
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| 107 |
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| 108 | false & wait
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| 109 |
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| 110 | { false; echo async; } & wait
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| 111 |
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| 112 | false
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| 113 | echo ok
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| 114 |
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| 115 | ## STDOUT:
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| 116 | subshell
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| 117 | async
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| 118 | line=11
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| 119 | ok
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| 120 | ## END
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| 121 |
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| 122 | #### trap ERR not active in shell functions in (bash behavior)
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| 123 |
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| 124 | trap 'echo line=$LINENO' ERR
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| 125 |
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| 126 | f() {
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| 127 | false
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| 128 | true
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| 129 | }
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| 130 |
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| 131 | f
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| 132 |
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| 133 | ## STDOUT:
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| 134 | ## END
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| 135 |
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| 136 | ## N-I mksh STDOUT:
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| 137 | line=4
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| 138 | ## END
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| 139 |
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| 140 | #### trap ERR shell function - with errtrace
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| 141 |
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| 142 | trap 'echo line=$LINENO' ERR
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| 143 |
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| 144 | passing() {
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| 145 | false # line 4
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| 146 | true
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| 147 | }
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| 148 |
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| 149 | failing() {
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| 150 | true
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| 151 | false
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| 152 | }
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| 153 |
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| 154 | passing
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| 155 | failing
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| 156 |
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| 157 | set -o errtrace
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| 158 |
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| 159 | echo 'now with errtrace'
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| 160 | passing
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| 161 | failing
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| 162 |
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| 163 | echo ok
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| 164 |
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| 165 | ## STDOUT:
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| 166 | line=14
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| 167 | now with errtrace
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| 168 | line=4
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| 169 | line=10
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| 170 | line=20
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| 171 | ok
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| 172 | ## END
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| 173 |
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| 174 | ## BUG mksh status: 1
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| 175 | ## BUG mksh STDOUT:
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| 176 | line=4
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| 177 | line=10
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| 178 | ## END
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| 179 |
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| 180 |
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| 181 | #### trap ERR with YSH proc
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| 182 |
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| 183 | case $SH in bash|mksh|ash) exit ;; esac
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| 184 |
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| 185 | # seems the same
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| 186 |
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| 187 | shopt -s ysh:upgrade
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| 188 |
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| 189 | proc abc { echo abc }
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| 190 | if test -f /nope { echo file exists }
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| 191 | trap abc ERR
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| 192 | if test -f /nope { echo file exists }
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| 193 |
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| 194 | ## STDOUT:
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| 195 | abc
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| 196 | ## END
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| 197 |
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| 198 | ## N-I bash/mksh/ash STDOUT:
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| 199 | ## END
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| 200 |
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| 201 | #### trap ERR
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| 202 | err() {
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| 203 | echo "err [$@] $?"
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| 204 | }
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| 205 | trap 'err x y' ERR
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| 206 |
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| 207 | echo A
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| 208 |
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| 209 | false
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| 210 | echo B
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| 211 |
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| 212 | ( exit 42 )
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| 213 | echo C
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| 214 |
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| 215 | trap - ERR # disable trap
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| 216 |
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| 217 | false
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| 218 | echo D
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| 219 |
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| 220 | trap 'echo after errexit $?' ERR
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| 221 |
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| 222 | set -o errexit
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| 223 |
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| 224 | ( exit 99 )
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| 225 | echo E
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| 226 |
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| 227 | ## status: 99
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| 228 | ## STDOUT:
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| 229 | A
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| 230 | err [x y] 1
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| 231 | B
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| 232 | err [x y] 42
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| 233 | C
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| 234 | D
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| 235 | after errexit 99
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| 236 | ## END
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| 237 | ## N-I dash STDOUT:
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| 238 | A
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| 239 | B
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| 240 | C
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| 241 | D
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| 242 | ## END
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| 243 |
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| 244 | #### trap ERR and pipelines (lastpipe and PIPESTATUS difference)
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| 245 | case $SH in ash) exit ;; esac
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| 246 |
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| 247 | err() {
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| 248 | echo "err [$@] status=$? [${PIPESTATUS[@]}]"
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| 249 | }
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| 250 | trap 'err' ERR
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| 251 |
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| 252 | echo A
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| 253 |
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| 254 | false
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| 255 |
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| 256 | # succeeds
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| 257 | echo B | grep B
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| 258 |
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| 259 | # fails
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| 260 | echo C | grep zzz
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| 261 |
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| 262 | echo D | grep zzz | cat
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| 263 |
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| 264 | set -o pipefail
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| 265 | echo E | grep zzz | cat
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| 266 |
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| 267 | trap - ERR # disable trap
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| 268 |
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| 269 | echo F | grep zz
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| 270 | echo ok
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| 271 |
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| 272 | ## STDOUT:
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| 273 | A
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| 274 | err [] status=1 [1]
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| 275 | B
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| 276 | err [] status=1 [0 1]
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| 277 | err [] status=1 [0 1 0]
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| 278 | ok
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| 279 | ## END
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| 280 |
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| 281 | # lastpipe semantics mean we get another call!
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| 282 | # also we don't set PIPESTATUS unless we get a pipeline
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| 283 |
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| 284 | ## OK osh STDOUT:
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| 285 | A
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| 286 | err [] status=1 []
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| 287 | B
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| 288 | err [] status=1 [0 0]
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| 289 | err [] status=1 [0 1]
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| 290 | err [] status=1 [0 1 0]
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| 291 | ok
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| 292 | ## END
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| 293 |
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| 294 | ## N-I ash STDOUT:
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| 295 | ## END
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| 296 |
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| 297 | #### error in trap ERR (recursive)
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| 298 | case $SH in dash) exit ;; esac
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| 299 |
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| 300 | err() {
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| 301 | echo err status $?
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| 302 | ( exit 2 )
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| 303 | }
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| 304 | trap 'err' ERR
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| 305 |
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| 306 | echo A
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| 307 | false
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| 308 | echo B
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| 309 |
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| 310 | ## STDOUT:
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| 311 | A
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| 312 | err status 1
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| 313 | B
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| 314 | ## END
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| 315 | ## N-I dash STDOUT:
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| 316 | ## END
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| 317 |
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