Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4571 5725 echo hi 02 90 100 114 117 207 232 250 4634 4619 date 03 90 100 114 131 207 232 250 4634 4619 date ; 04 98 116 123 132 269 292 281 4636 4636 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4636 4636 date; echo hi 06 91 104 115 132 209 256 254 4636 4621 echo hi; date 07 132 149 158 189 268 313 318 4684 4669 date; date 08 132 149 158 189 292 313 319 4684 4669 { date; date; } 09 132 149 158 189 292 313 319 4684 4669 date; { date; } 10 149 171 175 198 310 331 373 4696 4696 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4571 4571 (echo hi) 12 90 101 114 133 239 262 256 4634 4619 (date) 13 90 102 114 133 247 270 262 4634 4619 ( ( date ) ) 14 98 114 123 134 249 272 290 4636 4636 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4636 4621 echo hi; (date) 16 91 105 115 134 241 264 260 4636 4621 echo hi; (date;) 17 41 53 65 74 175 185 207 4586 4572 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4637 4622 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4587 4587 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4643 4626 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4643 4626 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4713 4694 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4580 4580 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4594 4580 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4666 4647 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4636 4636 (date; echo hi) 27 106 124 131 154 250 292 293 4643 4643 echo $(date) 28 55 73 81 93 185 194 237 4594 4594 echo $(echo hi) 29 106 125 131 154 279 300 299 4643 4643 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4660 4660 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4587 4587 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4706 4687 date | wc -l 33 157 177 183 226 318 352 360 4571 4706 ! date | wc -l 34 107 112 133 167 261 282 310 4657 4638 echo a | wc -l 35 107 112 133 167 261 282 353 4657 4638 command echo a | wc -l 36 157 170 183 226 318 380 360 4706 4687 command date | wc -l 37 157 186 183 227 318 380 360 4571 4706 ! command date | wc -l 38 157 162 183 226 326 360 367 4706 4687 ( date ) | wc -l 39 140 171 195 200 298 318 319 4676 4676 date | read x 40 108 115 134 168 262 283 289 4658 4639 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4660 4660 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4709 4690 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4658 4639 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4658 4639 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4659 4640 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4586 4586 echo hi & wait 47 104 117 128 142 258 280 283 4635 4635 date & wait 48 117 137 139 178 287 307 325 4654 4654 echo hi | wc -l & wait 49 167 184 189 237 344 377 374 4703 4703 date | wc -l & wait 50 105 125 129 143 296 318 290 4637 4637 trap 'echo mytrap' EXIT; date & wait 51 172 195 190 238 398 431 381 4705 4705 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4649 4649 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5490 6235 6800 8061 13481 14764 15230 241475 242444