Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4624 5814 echo hi 02 90 100 114 117 207 232 250 4687 4672 date 03 90 100 114 131 207 232 250 4687 4672 date ; 04 98 116 123 132 269 292 281 4687 4687 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4689 4689 date; echo hi 06 91 104 115 132 209 256 254 4689 4674 echo hi; date 07 132 149 158 189 268 313 318 4737 4722 date; date 08 132 149 158 189 292 313 319 4737 4722 { date; date; } 09 132 149 158 189 292 313 319 4737 4722 date; { date; } 10 149 171 175 198 310 331 373 4749 4749 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4624 4624 (echo hi) 12 90 101 114 133 239 262 256 4687 4672 (date) 13 90 102 114 133 247 270 262 4687 4672 ( ( date ) ) 14 98 114 123 134 249 272 290 4687 4687 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4689 4674 echo hi; (date) 16 91 105 115 134 241 264 260 4689 4674 echo hi; (date;) 17 41 53 65 74 175 185 207 4639 4625 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4688 4673 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4638 4638 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4694 4677 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4694 4677 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4764 4745 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4631 4631 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4645 4631 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4717 4698 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4689 4689 (date; echo hi) 27 106 124 131 154 250 292 293 4696 4696 echo $(date) 28 55 73 81 93 185 194 237 4647 4647 echo $(echo hi) 29 106 125 131 154 279 300 299 4696 4696 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4711 4711 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4638 4638 ( echo hi ); echo done 32 157 162 183 227 318 352 360 4759 4740 date | wc -l 33 157 177 183 226 318 352 360 4624 4759 ! date | wc -l 34 107 112 133 167 261 282 310 4710 4691 echo a | wc -l 35 107 112 133 167 261 282 353 4709 4689 command echo a | wc -l 36 157 170 183 226 318 380 360 4757 4738 command date | wc -l 37 157 186 183 227 318 380 360 4622 4757 ! command date | wc -l 38 157 162 183 226 326 360 367 4759 4740 ( date ) | wc -l 39 140 171 195 200 298 318 319 4729 4729 date | read x 40 108 115 134 168 262 283 289 4709 4690 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4711 4711 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4760 4741 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4709 4690 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4709 4690 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4710 4691 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4639 4639 echo hi & wait 47 104 117 128 142 258 280 283 4688 4688 date & wait 48 117 137 139 178 287 307 325 4705 4705 echo hi | wc -l & wait 49 167 188 189 238 344 377 374 4756 4756 date | wc -l & wait 50 105 125 129 143 296 318 290 4688 4688 trap 'echo mytrap' EXIT; date & wait 51 171 195 190 238 398 431 381 4756 4756 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4700 4700 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5489 6239 6800 8063 13481 14764 15230 244182 245186