Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4639 5850 echo hi 02 90 100 114 117 207 232 250 4702 4686 date 03 90 100 114 131 207 232 250 4702 4686 date ; 04 98 116 123 132 269 292 281 4704 4703 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4708 4707 date; echo hi 06 91 104 115 132 209 256 254 4708 4692 echo hi; date 07 132 149 158 189 268 313 318 4752 4736 date; date 08 132 149 158 189 292 313 319 4756 4740 { date; date; } 09 132 149 158 189 292 313 319 4756 4740 date; { date; } 10 149 171 175 198 310 331 373 4768 4767 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4639 4638 (echo hi) 12 90 101 114 133 239 262 256 4702 4686 (date) 13 90 102 114 133 247 270 262 4706 4690 ( ( date ) ) 14 98 114 123 134 249 272 290 4704 4703 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4708 4692 echo hi; (date) 16 91 105 115 134 241 264 260 4708 4692 echo hi; (date;) 17 41 53 65 74 175 185 207 4658 4643 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4705 4689 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4655 4654 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4711 4693 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4711 4693 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4781 4761 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4648 4647 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4662 4647 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4734 4714 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4708 4707 (date; echo hi) 27 106 124 131 154 250 292 293 4715 4714 echo $(date) 28 55 73 81 93 185 194 237 4666 4665 echo $(echo hi) 29 106 125 131 154 279 300 299 4715 4714 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4728 4727 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4655 4654 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4778 4758 date | wc -l 33 157 178 183 226 318 352 360 4643 4777 ! date | wc -l 34 107 112 133 167 261 282 310 4729 4709 echo a | wc -l 35 107 112 133 167 261 282 353 4725 4705 command echo a | wc -l 36 157 170 183 226 318 380 360 4774 4754 command date | wc -l 37 157 186 183 226 318 380 360 4639 4773 ! command date | wc -l 38 157 162 183 226 326 360 367 4778 4758 ( date ) | wc -l 39 140 171 195 200 298 318 319 4748 4747 date | read x 40 108 115 134 168 262 283 289 4726 4706 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4728 4727 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4777 4757 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4726 4706 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4726 4706 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4725 4705 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4658 4657 echo hi & wait 47 104 117 128 142 258 280 283 4703 4702 date & wait 48 117 137 139 178 287 307 325 4722 4721 echo hi | wc -l & wait 49 167 184 189 237 344 377 374 4775 4774 date | wc -l & wait 50 105 125 129 143 296 318 290 4705 4704 trap 'echo mytrap' EXIT; date & wait 51 168 196 190 238 398 431 381 4771 4770 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4717 4716 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5486 6237 6800 8060 13481 14764 15230 245087 246062