Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4599 5793 echo hi 02 90 100 114 117 207 232 250 4662 4647 date 03 90 100 114 131 207 232 250 4662 4647 date ; 04 98 116 123 132 269 292 281 4664 4664 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4664 4664 date; echo hi 06 91 104 115 132 209 256 254 4664 4649 echo hi; date 07 132 149 158 189 268 313 318 4712 4697 date; date 08 132 149 158 189 292 313 319 4712 4697 { date; date; } 09 132 149 158 189 292 313 319 4712 4697 date; { date; } 10 149 171 175 198 310 331 373 4724 4724 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4599 4599 (echo hi) 12 90 101 114 133 239 262 256 4662 4647 (date) 13 90 102 114 133 247 270 262 4662 4647 ( ( date ) ) 14 98 114 123 134 249 272 290 4664 4664 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4664 4649 echo hi; (date) 16 91 105 115 134 241 264 260 4664 4649 echo hi; (date;) 17 41 53 65 74 175 185 207 4614 4600 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4665 4650 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4615 4615 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4671 4654 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4671 4654 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4741 4722 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4608 4608 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4622 4608 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4694 4675 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4664 4664 (date; echo hi) 27 106 124 131 154 250 292 293 4671 4671 echo $(date) 28 55 73 81 93 185 194 237 4622 4622 echo $(echo hi) 29 106 125 131 154 279 300 299 4671 4671 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4688 4688 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4615 4615 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4734 4715 date | wc -l 33 157 178 183 226 318 352 360 4599 4734 ! date | wc -l 34 107 112 133 167 261 282 310 4685 4666 echo a | wc -l 35 107 112 133 167 261 282 353 4685 4666 command echo a | wc -l 36 157 170 183 226 318 380 360 4734 4715 command date | wc -l 37 157 186 183 226 318 380 360 4599 4734 ! command date | wc -l 38 157 162 183 226 326 360 367 4734 4715 ( date ) | wc -l 39 140 171 195 200 298 318 319 4704 4704 date | read x 40 108 115 134 168 262 283 289 4686 4667 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4689 4688 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4736 4718 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4686 4667 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4686 4667 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 305 4687 4668 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4614 4614 echo hi & wait 47 104 117 128 142 258 280 283 4663 4663 date & wait 48 117 137 139 178 287 307 325 4682 4682 echo hi | wc -l & wait 49 171 184 189 237 344 377 374 4731 4731 date | wc -l & wait 50 105 125 129 143 296 318 290 4665 4665 trap 'echo mytrap' EXIT; date & wait 51 169 196 190 238 398 431 381 4733 4733 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4677 4677 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5491 6237 6800 8060 13481 14764 15232 242931 243940