Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4602 5802 echo hi 02 90 100 114 117 207 232 250 4665 4650 date 03 90 100 114 131 207 232 250 4665 4650 date ; 04 98 116 123 132 269 292 281 4679 4679 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4683 4683 date; echo hi 06 91 104 115 132 209 256 254 4683 4668 echo hi; date 07 132 149 158 189 268 313 318 4715 4700 date; date 08 132 149 158 189 292 313 319 4731 4716 { date; date; } 09 132 149 158 189 292 313 319 4731 4716 date; { date; } 10 149 171 175 198 310 331 373 4743 4743 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4602 4602 (echo hi) 12 90 101 114 133 239 262 256 4665 4650 (date) 13 90 102 114 133 247 270 262 4681 4666 ( ( date ) ) 14 98 114 123 134 249 272 290 4679 4679 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4683 4668 echo hi; (date) 16 91 105 115 134 241 264 260 4683 4668 echo hi; (date;) 17 41 53 65 74 175 185 207 4633 4619 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4680 4665 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4630 4630 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4686 4669 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4686 4669 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4756 4737 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4623 4623 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4637 4623 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4709 4690 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4683 4683 (date; echo hi) 27 106 124 131 154 250 292 293 4690 4690 echo $(date) 28 55 73 81 93 185 194 237 4641 4641 echo $(echo hi) 29 106 125 131 154 279 300 299 4690 4690 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4703 4703 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4630 4630 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4753 4734 date | wc -l 33 157 177 183 226 318 352 360 4618 4753 ! date | wc -l 34 107 112 133 167 261 282 310 4704 4685 echo a | wc -l 35 107 112 133 167 261 282 353 4700 4681 command echo a | wc -l 36 157 170 183 226 318 380 360 4749 4730 command date | wc -l 37 157 186 183 226 318 380 360 4614 4749 ! command date | wc -l 38 157 162 183 226 326 360 367 4753 4734 ( date ) | wc -l 39 140 171 195 200 298 318 319 4723 4723 date | read x 40 108 115 134 168 262 283 289 4701 4682 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4703 4703 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4751 4733 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4701 4682 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4701 4682 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4702 4683 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4633 4633 echo hi & wait 47 104 117 128 142 258 280 283 4666 4666 date & wait 48 117 137 139 178 287 307 325 4697 4697 echo hi | wc -l & wait 49 167 184 189 237 344 377 374 4750 4750 date | wc -l & wait 50 105 125 129 143 296 318 290 4680 4680 trap 'echo mytrap' EXIT; date & wait 51 168 195 190 238 398 431 381 4748 4748 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4692 4692 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5486 6235 6800 8060 13481 14764 15230 243706 244722