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 5701 echo hi 02 90 100 114 117 207 232 250 4637 4619 date 03 90 100 114 131 207 232 250 4637 4619 date ; 04 98 116 123 132 269 292 281 4639 4639 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4637 4637 date; echo hi 06 91 104 115 132 209 256 254 4637 4619 echo hi; date 07 132 149 158 189 268 313 318 4690 4672 date; date 08 132 149 158 189 292 313 319 4688 4670 { date; date; } 09 132 149 158 189 292 313 319 4688 4670 date; { date; } 10 149 171 175 198 310 331 373 4700 4700 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4571 4571 (echo hi) 12 90 101 114 133 239 262 256 4637 4619 (date) 13 90 102 114 133 247 270 262 4635 4617 ( ( date ) ) 14 98 114 123 134 249 272 290 4639 4639 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4637 4619 echo hi; (date) 16 91 105 115 134 241 264 260 4637 4619 echo hi; (date;) 17 41 53 65 74 175 185 207 4587 4570 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4640 4622 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4590 4590 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4646 4626 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4646 4626 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4719 4697 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 4597 4580 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4672 4650 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4637 4637 (date; echo hi) 27 106 124 131 154 250 292 293 4642 4642 echo $(date) 28 55 73 81 93 185 194 237 4593 4593 echo $(echo hi) 29 106 125 131 154 279 300 299 4642 4642 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4664 4664 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4590 4590 ( echo hi ); echo done 32 157 162 183 227 318 352 360 4710 4688 date | wc -l 33 157 177 183 227 318 352 360 4569 4710 ! date | wc -l 34 107 112 133 167 261 282 310 4661 4639 echo a | wc -l 35 107 112 133 167 261 282 353 4663 4641 command echo a | wc -l 36 157 170 183 227 318 380 360 4712 4690 command date | wc -l 37 157 186 183 227 318 380 360 4571 4712 ! command date | wc -l 38 157 162 183 226 326 360 367 4710 4688 ( date ) | wc -l 39 140 171 195 200 298 318 319 4678 4678 date | read x 40 108 115 134 168 262 283 289 4664 4642 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4667 4666 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4715 4693 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4664 4642 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4664 4642 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4665 4643 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4585 4585 echo hi & wait 47 104 117 128 142 258 280 283 4636 4636 date & wait 48 117 137 139 178 287 307 325 4655 4655 echo hi | wc -l & wait 49 171 188 189 237 344 377 374 4702 4702 date | wc -l & wait 50 105 125 129 143 296 318 290 4638 4638 trap 'echo mytrap' EXIT; date & wait 51 168 196 190 238 398 431 381 4706 4706 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4653 4653 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5490 6240 6800 8064 13481 14764 15230 241613 242488