Shell implementation Multi-threaded (multi-tasking)

Implementation scenario: 1. Add:& at the end of the command

#/bin/Bashall_num=Tena=$(Date+%h%m%S) forNuminch`seq 1${all_num} ' Do {    Sleep 1    Echo${num}}& Doneb=$(Date+%h%m%S)Echo-E"starttime:\t$a"Echo-E"endtime:\t$b"

With the & symbol at the end of the command, the command executes in the background so that subsequent commands do not have to wait for the command to finish before starting execution.

2. Resolve the main thread early exit problem, add wait

#/bin/Bashall_num=Tena=$(Date+%h%m%S) forNuminch`seq 1${all_num} ' Do {    Sleep 1    Echo${num}}&# The command is executed in the background and the command range is surrounded by {} Done# Wait for the child process to end under the current script processwaitb=$(Date+%h%m%S)Echo-E"starttime:\t$a"Echo-E"endtime:\t$b"

3. Control the number of background executions (number of threads), Mkfifo

#/bin/Bashall_num=Ten# Set the number of concurrent processes Thread_num=5a=$(Date+%h%m%S) #MkfifoTempfifo="My_temp_fifo"Mkfifo${tempfifo}# to make file descriptors non-blocking exec6<>${tempfifo}RM-f ${tempfifo}# Creating placeholder information for file descriptors for((i=1; i<=${thread_num};i++)) Do{    Echo } Done>&6 #  forNuminch`seq 1${all_num} ' Do{Read-U6 {Sleep 1        Echo${num}Echo "">&6    } & }  Done wait# close FD6 pipe exec6>&-b=$(Date+%h%m%S)Echo-E"starttime:\t$a"Echo-E"endtime:\t$b"

Resources

[1] Scenario Linux--shell How to achieve multithreading?

[2] linux-shell-using Mkfifo for multitasking concurrency and concurrency control

Shell implementation Multi-threaded (multi-tasking)