Linux script that monitors file changes in folders (e.g. autospec!)

Question

I want to automatically run the assembly every time the file is changed.

I used autospec (RSpec) in Ruby and loved this.

How can this be done in bash?

Answer 1

After reading the answers to other posts, I found a message (now gone), I created this script: -

#!/bin/bash sha=0 previous_sha=0 update_sha() { sha=`ls -lR . | sha1sum` } build () { ## Build/make commands here echo echo "--> Monitor: Monitoring filesystem... (Press enter to force a build/update)" } changed () { echo "--> Monitor: Files changed, Building..." build previous_sha=$sha } compare () { update_sha if [[ $sha != $previous_sha ]] ; then changed; fi } run () { while true; do compare read -s -t 1 && ( echo "--> Monitor: Forced Update..." build ) done } echo "--> Monitor: Init..." echo "--> Monitor: Monitoring filesystem... (Press enter to force a build/update)" run 

Answer 2

Take a look at incron and inotify-tools .

Answer 3

keywords - inotifywait and inotifywatch commands

Answer 4

How about this script? Uses the "stat" command to get the file access time and runs the command whenever the access time changes (each time the file is accessed).

 #!/bin/bash while true do ATIME=`stat -c %Z /path/to/the/file.txt` if [[ "$ATIME" != "$LTIME" ]] then echo "RUN COMMNAD" LTIME=$ATIME fi sleep 5 done 

Answer 5

See this example as an improvement on Jan Vaughan's answer:

 #!/usr/bin/env bash # script: watch # author: Mike Smullin <[e-mail]> # license: GPLv3 # description: # watches the given path for changes # and executes a given command when changes occur # usage: # watch <path> <cmd...> # path=$1 shift cmd=$* sha=0 update_sha() { sha=`ls -lR --time-style=full-iso $path | sha1sum` } update_sha previous_sha=$sha build() { echo -en " building...\n\n" $cmd echo -en "\n--> resumed watching." } compare() { update_sha if [[ $sha != $previous_sha ]] ; then echo -n "change detected," build previous_sha=$sha else echo -n . fi } trap build SIGINT trap exit SIGQUIT echo -e "--> Press Ctrl+C to force build, Ctrl+\\ to exit." echo -en "--> watching \"$path\"." while true; do compare sleep 1 done 

Answer 6

If you installed entr , then in the shell you can use the following syntax:

 while true; do find src/ | entr -d make build; done