Waits for write/rename events on files or directories and returns.
Supports waiting on multiple files and one directory (I'm on it). When waiting on a directory, adding a file, or deleting a file will trigger a return. Everything else (like touching or writing) will not trigger a return.
This tool is inspired by inotifywait, the original kqueue paper, and the lack of anything similar (to the best of my knowledge) on Mac OS X.
- Xcode
Waiting on directories does not work on Linux at the moment.
To build this just type:
make
Call it like this:
kqwait <file>[ <file>]+
or this:
kqwait <dir>[ <dir>]+
Prints the file or directory that caused the tool to wake up, and
returns 0, if the expected event occured, 1 otherwise.
When waiting on a directory, a + character is prepended if a file was
added, a - if a file was deleted.
Use it in a shell script like this:
while ./kqwait text.txt; do
# do some stuff on write
done
Or watch directories like this:
$ while ./kqwait somedir someother; do true; done
+ somedir/a_file_was_added.txt
- someotherdir/a_file_was_deleted.txt
There is (at least) one race condition in this code, when waiting for changes on directories. If several events happen on a directory in quick succession, this tool might catch an intermediate snapshot of that chain of events.
Sven Schober sven.schober@uni-ulm.de
Copyright (c) 2013, Sven Schober
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