c - Counting processes after fork in for loop -


i have following code:

for(i=1; i<=2; i++) {     fork();     printf("x ");    }

i calculated x should printed out 6 times: twice in first iteration , 4 times in second.

instead, x printed 8 times. why?

because of buffering. usually, stdout line-buffered, so

printf("x ");

doesn't write "x " terminal output buffer. copied when process fork()s, each of 4 processes after second iteration has 2 "x " in output buffer [one parent/before forking in first iteration, 1 second iteration] when exits , 8 xs printed altogether.

flush buffer after printf("x "); , 6 printed.


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