24 lines
605 B
C++
24 lines
605 B
C++
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <signal.h>
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int main(int argc, char* argv[])
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{
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pid_t slavepid = fork();
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if ( slavepid < 0 ) { perror("fork"); return 1; }
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if ( slavepid == 0 ) { while ( true ) { usleep(0); } exit(0); }
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uintmax_t start;
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if ( uptime(&start) ) { perror("uptime"); return 1; }
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uintmax_t end = start + 1ULL * 1000ULL; // 1 second
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size_t count = 0;
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uintmax_t now;
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while ( !uptime(&now) && now < end ) { usleep(0); count += 2; /* back and forth */ }
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printf("Made %zu context switches in 1 second\n", count);
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kill(slavepid, SIGKILL);
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return 0;
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}
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