Number of Syscalls ID dash yash ash mksh bash-5 bash-4 zsh ysh osh Description 01 40 49 64 59 144 156 194 4611 5736 echo hi 02 90 100 114 117 207 232 250 4674 4659 date 03 90 100 114 131 207 232 250 4674 4659 date ; 04 98 116 123 132 269 292 281 4702 4702 trap 'echo mytrap' EXIT; date 05 98 112 123 132 233 256 278 4694 4694 date; echo hi 06 91 104 115 132 209 256 254 4694 4679 echo hi; date 07 132 149 158 189 268 313 318 4724 4709 date; date 08 132 149 158 189 292 313 319 4742 4727 { date; date; } 09 132 149 158 189 292 313 319 4742 4727 date; { date; } 10 149 171 175 198 310 331 373 4754 4754 . _tmp/sourced.sh 11 40 50 64 73 174 184 203 4611 4611 (echo hi) 12 90 101 114 133 239 262 256 4674 4659 (date) 13 90 102 114 133 247 270 262 4692 4677 ( ( date ) ) 14 98 114 123 134 249 272 290 4710 4710 ( ( date ) ); echo hi 15 91 105 115 134 241 264 260 4694 4679 echo hi; (date) 16 91 105 115 134 241 264 260 4694 4679 echo hi; (date;) 17 41 53 65 74 175 185 207 4644 4630 echo hi; (echo hi;) 18 92 108 116 147 242 285 264 4711 4696 echo hi; (echo hi; date) 19 48 62 73 74 176 186 231 4661 4661 ( echo hi ); echo hi 20 96 105 118 139 234 257 256 4717 4700 date > /tmp/redir.txt 21 93 119 117 141 242 265 259 4717 4700 (date;) > /tmp/sentence.txt 22 163 167 187 231 321 355 363 4779 4760 date 2> /tmp/stderr.txt | wc -l 23 48 57 70 66 154 166 201 4654 4654 echo hi > /tmp/redir.txt 24 43 60 67 81 177 187 205 4660 4646 (echo hi;) > /tmp/sentence.txt 25 115 119 139 174 264 285 312 4732 4713 echo hi 2> /tmp/stderr.txt | wc -l 26 98 113 123 146 262 284 287 4694 4694 (date; echo hi) 27 106 124 131 154 250 292 293 4701 4701 echo $(date) 28 55 73 81 93 185 194 237 4652 4652 echo $(echo hi) 29 106 125 131 154 279 300 299 4701 4701 echo $( ( date ) ) 30 114 138 140 169 282 303 328 4734 4734 echo $( ( date ); echo hi ) 31 48 62 73 74 176 186 231 4661 4661 ( echo hi ); echo done 32 157 162 183 226 318 352 360 4764 4745 date | wc -l 33 157 178 183 226 318 352 360 4629 4764 ! date | wc -l 34 107 112 133 167 261 282 310 4715 4696 echo a | wc -l 35 107 112 133 167 261 282 353 4731 4712 command echo a | wc -l 36 157 170 183 226 318 380 360 4780 4761 command date | wc -l 37 157 186 183 226 318 380 360 4645 4780 ! command date | wc -l 38 157 162 183 226 326 360 367 4764 4745 ( date ) | wc -l 39 140 171 195 200 298 318 319 4734 4734 date | read x 40 108 115 134 168 262 283 289 4732 4713 { echo a; echo b; } | wc -l 41 110 132 135 169 264 285 320 4728 4728 { echo a; echo b; } | wc -l; echo done 42 159 167 185 241 350 383 344 4783 4764 { echo a; date; } | wc -l 43 108 115 134 168 262 283 317 4732 4713 ( echo a; echo b ) | wc -l 44 108 116 134 168 272 293 324 4724 4705 ( echo a; echo b ) | ( wc -l ) 45 109 120 135 183 302 322 303 4727 4708 { echo prefix; ( echo a; echo b ); } | ( wc -l ) 46 54 66 78 82 201 210 233 4644 4644 echo hi & wait 47 104 117 128 142 258 280 283 4675 4675 date & wait 48 117 137 139 178 287 307 325 4728 4728 echo hi | wc -l & wait 49 170 188 189 237 344 377 374 4761 4761 date | wc -l & wait 50 105 125 129 143 296 318 290 4705 4705 trap 'echo mytrap' EXIT; date & wait 51 169 195 190 238 398 431 381 4773 4773 trap 'echo mytrap' EXIT; date | wc -l & wait 52 112 133 136 153 326 346 318 4717 4717 { trap 'echo mytrap' EXIT; date; } & wait TOTAL 5490 6240 6800 8060 13481 14764 15230 244695 245635