Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4591 5779 echo hi 02 90 100 114 117 207 232 250 4654 4639 date 03 90 100 114 131 207 232 250 4654 4639 date ; 04 98 116 123 132 269 292 281 4658 4658 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4658 4658 date; echo hi 06 91 104 115 132 209 256 254 4658 4643 echo hi; date 07 132 149 158 189 268 313 318 4704 4689 date; date 08 132 149 158 189 292 313 319 4706 4691 { date; date; } 09 132 149 158 189 292 313 319 4706 4691 date; { date; } 10 149 171 175 198 310 331 373 4718 4718 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4591 4591 (echo hi) 12 90 101 114 133 239 262 256 4654 4639 (date) 13 90 102 114 133 247 270 262 4656 4641 ( ( date ) ) 14 98 114 123 134 249 272 290 4658 4658 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4658 4643 echo hi; (date) 16 91 105 115 134 241 264 260 4658 4643 echo hi; (date;) 17 41 53 65 74 175 185 207 4608 4594 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4659 4644 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4609 4609 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4665 4648 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4665 4648 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4735 4716 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4602 4602 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4616 4602 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4688 4669 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4658 4658 (date; echo hi) 27 106 124 131 154 250 292 293 4665 4665 echo $(date) 28 55 73 81 93 185 194 237 4616 4616 echo $(echo hi) 29 106 125 131 154 279 300 299 4665 4665 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4682 4682 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4609 4609 ( echo hi ); echo done 32 157 162 183 227 318 352 360 4728 4709 date | wc -l 33 157 178 183 226 318 352 360 4593 4728 ! date | wc -l 34 107 112 133 167 261 282 310 4679 4660 echo a | wc -l 35 107 112 133 167 261 282 353 4679 4660 command echo a | wc -l 36 157 170 183 227 318 380 360 4728 4709 command date | wc -l 37 157 186 183 226 318 380 360 4593 4728 ! command date | wc -l 38 157 162 183 226 326 360 367 4728 4709 ( date ) | wc -l 39 140 171 195 200 298 318 319 4698 4698 date | read x 40 108 115 134 168 262 283 289 4680 4661 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4682 4682 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4731 4712 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4680 4661 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4680 4661 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4681 4662 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4608 4608 echo hi & wait 47 104 117 128 142 258 280 283 4655 4655 date & wait 48 117 137 139 178 287 307 325 4676 4676 echo hi | wc -l & wait 49 171 184 189 237 344 377 374 4725 4725 date | wc -l & wait 50 105 125 129 143 296 318 290 4659 4659 trap 'echo mytrap' EXIT; date & wait 51 168 195 190 239 398 431 381 4727 4727 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4671 4671 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5490 6236 6800 8063 13481 14764 15230 242605 243608