COMP 3000 Lab 6 2012: Difference between revisions
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Run the following three commands in bash. (Note the \ is just to note the command continues on the following line.) | Run the following three commands in bash. (Note the \ is just to note the command continues on the following line.) | ||
x=0; while builtin test $x -lt 50000; do echo "P1 C1 $x"; echo "P1 C2 $x"; \ | x=0; while builtin test $x -lt 50000; do echo "P1 C1 $x"; echo "P1 C2 $x"; \ | ||
echo "P1 C3 $x"; let x=$(($x + 1)); done >> race.txt & | echo "P1 C3 $x"; let x=$(($x + 1)); done >> race.txt & | ||
y=0; while builtin test $y -lt 50000; do echo "P2 C1 $y"; echo "P2 C2 $ | y=0; while builtin test $y -lt 50000; do echo "P2 C1 $y"; echo "P2 C2 $y"; \ | ||
echo "P2 C3 $ | echo "P2 C3 $y"; let y=$(($y + 1)); done >> race.txt & | ||
The following questions are based on these three lines. | The following questions are based on these three lines. | ||
# Describe the output of the above lines. In particular, how is the output of the two commands intermingled in the file race.txt? | |||
# How could you modify the lines so that output to the file race.txt continues until a file "done" is created in the current directory (instead of testing the values of x and y)? | |||
# How many processes do these two lines generate on your system? | |||
Revision as of 15:35, 5 November 2012
This lab is due on Friday, Nov. 9, at 11:55 PM.
Run the following three commands in bash. (Note the \ is just to note the command continues on the following line.)
x=0; while builtin test $x -lt 50000; do echo "P1 C1 $x"; echo "P1 C2 $x"; \ echo "P1 C3 $x"; let x=$(($x + 1)); done >> race.txt & y=0; while builtin test $y -lt 50000; do echo "P2 C1 $y"; echo "P2 C2 $y"; \ echo "P2 C3 $y"; let y=$(($y + 1)); done >> race.txt &
The following questions are based on these three lines.
- Describe the output of the above lines. In particular, how is the output of the two commands intermingled in the file race.txt?
- How could you modify the lines so that output to the file race.txt continues until a file "done" is created in the current directory (instead of testing the values of x and y)?
- How many processes do these two lines generate on your system?