File Events

File Events

FileWatching.poll_fdFunction.
poll_fd(fd, timeout_s::Real=-1; readable=false, writable=false)

Monitor a file descriptor fd for changes in the read or write availability, and with a timeout given by timeout_s seconds.

The keyword arguments determine which of read and/or write status should be monitored; at least one of them must be set to true.

The returned value is an object with boolean fields readable, writable, and timedout, giving the result of the polling.

poll_file(path::AbstractString, interval_s::Real=5.007, timeout_s::Real=-1) -> (previous::StatStruct, current)

Monitor a file for changes by polling every interval_s seconds until a change occurs or timeout_s seconds have elapsed. The interval_s should be a long period; the default is 5.007 seconds.

Returns a pair of status objects (previous, current) when a change is detected. The previous status is always a StatStruct, but it may have all of the fields zeroed (indicating the file didn't previously exist, or wasn't previously accessible).

The current status object may be a StatStruct, an EOFError (indicating the timeout elapsed), or some other Exception subtype (if the stat operation failed - for example, if the path does not exist).

To determine when a file was modified, compare current isa StatStruct && mtime(prev) != mtime(current) to detect notification of changes. However, using watch_file for this operation is preferred, since it is more reliable and efficient, although in some situations it may not be available.

watch_file(path::AbstractString, timeout_s::Real=-1)

Watch file or directory path for changes until a change occurs or timeout_s seconds have elapsed.

The returned value is an object with boolean fields changed, renamed, and timedout, giving the result of watching the file.

This behavior of this function varies slightly across platforms. See https://nodejs.org/api/fs.html#fs_caveats for more detailed information.

watch_folder(path::AbstractString, timeout_s::Real=-1)

Watches a file or directory path for changes until a change has occurred or timeout_s seconds have elapsed.

This will continuing tracking changes for path in the background until unwatch_folder is called on the same path.

The returned value is an pair where the first field is the name of the changed file (if available) and the second field is an object with boolean fields changed, renamed, and timedout, giving the event.

This behavior of this function varies slightly across platforms. See https://nodejs.org/api/fs.html#fs_caveats for more detailed information.

unwatch_folder(path::AbstractString)

Stop background tracking of changes for path. It is not recommended to do this while another task is waiting for watch_folder to return on the same path, as the result may be unpredictable.