Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4641 5868 echo hi 02 90 100 114 117 207 232 250 4704 4688 date 03 90 100 114 131 207 232 250 4704 4688 date ; 04 98 116 123 132 269 292 281 4706 4705 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4710 4709 date; echo hi 06 91 104 115 132 209 256 254 4710 4694 echo hi; date 07 132 149 158 189 268 313 318 4754 4738 date; date 08 132 149 158 189 292 313 319 4758 4742 { date; date; } 09 132 149 158 189 292 313 319 4758 4742 date; { date; } 10 149 171 175 198 310 331 373 4770 4769 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4641 4640 (echo hi) 12 90 101 114 133 239 262 256 4704 4688 (date) 13 90 102 114 133 247 270 262 4708 4692 ( ( date ) ) 14 98 114 123 134 249 272 290 4706 4705 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4710 4694 echo hi; (date) 16 91 105 115 134 241 264 260 4710 4694 echo hi; (date;) 17 41 53 65 74 175 185 207 4660 4645 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4707 4691 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4657 4656 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4713 4695 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4713 4695 (date;) > /tmp/sentence.txt 22 163 167 187 232 321 355 363 4783 4763 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4650 4649 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4664 4649 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4736 4716 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4710 4709 (date; echo hi) 27 106 124 131 154 250 292 293 4717 4716 echo $(date) 28 55 73 81 93 185 194 237 4668 4667 echo $(echo hi) 29 106 125 131 154 279 300 299 4717 4716 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4730 4729 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4657 4656 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4780 4760 date | wc -l 33 157 178 183 226 318 352 360 4645 4779 ! date | wc -l 34 107 112 133 167 261 282 310 4731 4711 echo a | wc -l 35 107 112 133 167 261 282 353 4727 4707 command echo a | wc -l 36 157 170 183 226 318 380 360 4776 4756 command date | wc -l 37 157 186 183 226 318 380 360 4641 4775 ! command date | wc -l 38 157 162 183 226 326 360 367 4780 4760 ( date ) | wc -l 39 140 171 195 200 298 318 319 4750 4749 date | read x 40 108 115 134 168 262 283 289 4728 4708 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4727 4725 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4779 4759 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4728 4708 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4728 4708 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4729 4709 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4660 4659 echo hi & wait 47 104 117 128 142 258 280 283 4705 4704 date & wait 48 117 137 139 178 287 307 325 4724 4723 echo hi | wc -l & wait 49 167 184 189 237 344 377 374 4777 4776 date | wc -l & wait 50 105 125 129 143 296 318 290 4703 4702 trap 'echo mytrap' EXIT; date & wait 51 169 196 190 238 398 431 381 4775 4774 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4715 4714 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5487 6237 6800 8061 13481 14764 15230 245184 246174