Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4603 5755 echo hi 02 90 100 114 117 207 232 250 4666 4650 date 03 90 100 114 131 207 232 250 4666 4651 date ; 04 98 116 123 132 269 292 281 4668 4668 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4650 4650 date; echo hi 06 91 104 115 132 209 256 254 4650 4635 echo hi; date 07 132 149 158 189 268 313 318 4716 4701 date; date 08 132 149 158 189 292 313 319 4698 4683 { date; date; } 09 132 149 158 189 292 313 319 4698 4683 date; { date; } 10 149 171 175 198 310 331 373 4710 4710 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4603 4603 (echo hi) 12 90 101 114 133 239 262 256 4666 4651 (date) 13 90 102 114 133 247 270 262 4648 4633 ( ( date ) ) 14 98 114 123 134 249 272 290 4671 4671 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4650 4635 echo hi; (date) 16 91 105 115 134 241 264 260 4650 4635 echo hi; (date;) 17 41 53 65 74 175 185 207 4600 4586 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4671 4656 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4622 4622 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4677 4660 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4678 4660 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4746 4726 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4614 4614 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4627 4612 (echo hi;) > /tmp/sentence.txt 25 115 120 139 174 264 285 312 4699 4680 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4650 4650 (date; echo hi) 27 106 124 131 154 250 292 293 4658 4658 echo $(date) 28 55 73 81 93 185 194 237 4609 4611 echo $(echo hi) 29 106 125 131 154 279 300 299 4658 4658 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4694 4695 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4622 4622 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4721 4702 date | wc -l 33 157 177 183 226 318 352 360 4584 4721 ! date | wc -l 34 107 112 133 167 261 282 310 4672 4653 echo a | wc -l 35 107 112 133 167 261 282 353 4692 4673 command echo a | wc -l 36 157 170 183 226 318 380 360 4741 4722 command date | wc -l 37 157 186 183 226 318 380 360 4604 4741 ! command date | wc -l 38 157 162 183 226 326 360 367 4720 4702 ( date ) | wc -l 39 140 171 195 200 298 318 319 4691 4691 date | read x 40 108 115 134 168 262 283 289 4692 4674 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4692 4692 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4743 4725 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4692 4673 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4690 4671 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4691 4672 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4601 4601 echo hi & wait 47 104 117 128 142 258 280 283 4668 4668 date & wait 48 117 137 139 178 287 307 325 4690 4690 echo hi | wc -l & wait 49 171 184 193 237 344 377 374 4721 4721 date | wc -l & wait 50 105 125 129 143 296 318 290 4669 4669 trap 'echo mytrap' EXIT; date & wait 51 168 196 194 238 398 431 381 4737 4737 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4682 4682 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5490 6237 6808 8060 13481 14764 15230 242831 243804