Help about bash process

Shell Programming and Scripting
1

I have function f1 and f2, I want it excute five items with different function in the list the the same time with process.

I did a testing in start_build_feature1, it sleep about 100s, in the sleeping start_build_feature2 print nothing, can someone help me modify this scripts

I don't when start_build_feature1 in the 100s sleep, start_build_feature2 do noting (nothing output in the screen) , I want somthing is parallel

please help me modify and explain it to me


start_build_feature1()
{
	sleep 100
	echo $1
}

start_build_feature2()
{
	echo $1
}

feature_single1="aa bb c d e f g h i g k l m n u v w x y z"
feature_single2="1 2 3 4 5 6 7 8 9 10 11 12 13 14 15"



f1()
{
        pid_feature1=()
        local i
        set -- $feature_single1 # NOte $lists IS NOT QUOTED here.

        while [ "$#" -gt 0 ]
        do
                [ ! -z "$1" ] && ((i += 1)) && start_build_feature1 "$1" & pid_feature1[$i]=$!
                [ ! -z "$2" ] && ((i += 1)) && start_build_feature1 "$2" & pid_feature1[$i]=$!
                [ ! -z "$3" ] && ((i += 1)) && start_build_feature1 "$3" & pid_feature1[$i]=$!
                [ ! -z "$4" ] && ((i += 1)) && start_build_feature1 "$4" & pid_feature1[$i]=$!
                [ ! -z "$5" ] && ((i += 1)) && start_build_feature1 "$5" & pid_feature1[$i]=$!
                shift 5
                for i in ${#pid_feature1[@]}
                do
                        wait ${pid_feature1[$i]}
			echo "start another five in feature_single1"
                done
        done
}

f2()
{
        pid_feature2=()
        local i
        set -- $feature_single2 # NOte $lists IS NOT QUOTED here.

        while [ "$#" -gt 0 ]
        do
                [ ! -z "$1" ] && ((i += 1)) && start_build_feature2 "$1" & pid_feature2[$i]=$!
                [ ! -z "$2" ] && ((i += 1)) && start_build_feature2 "$2" & pid_feature2[$i]=$!
                [ ! -z "$3" ] && ((i += 1)) && start_build_feature2 "$3" & pid_feature2[$i]=$!
                [ ! -z "$4" ] && ((i += 1)) && start_build_feature2 "$4" & pid_feature2[$i]=$!
                [ ! -z "$5" ] && ((i += 1)) && start_build_feature2 "$5" & pid_feature2[$i]=$!
                shift 5
                for i in ${#pid_feature2[@]}
                do
                        wait ${pid_feature2[$i]}
			echo "start another five in feature_single"
                done
        done
}
f1 &
f2
2

Looks like a job for GNU parallel. Who sets i initially and resets it for each 5? Wait will wait for all children of that process. Export variables being used in subshells.

3

Sorry for missing this.

What is the question? I don't understand.

Also, I don't understand your modifications either. Plain wait by itself will do the job, you don't need to wait for individual PID's.