user_cancel

cancel the current upload or download operation

This function cancels the current upload or download operation.

Unlike most other libguestfs calls, this function is signal safe and thread safe. You can call it from a signal handler or from another thread, without needing to do any locking.

The transfer that was in progress (if there is one) will stop shortly afterwards, and will return an error. The errno (see "guestfs_last_errno" ) is set to EINTR, so you can test for this to find out if the operation was cancelled or failed because of another error.

No cleanup is performed: for example, if a file was being uploaded then after cancellation there may be a partially uploaded file. It is the caller’s responsibility to clean up if necessary.

There are two common places that you might call user_cancel:

In an interactive text-based program, you might call it from a SIGINT signal handler so that pressing "^C" cancels the current operation. (You also need to call "guestfs_set_pgroup" so that child processes don't receive the "^C" signal).

In a graphical program, when the main thread is displaying a progress bar with a cancel button, wire up the cancel button to call this function.

Parameters:

this	A GuestfsSession object

Returns:

true on success, false on error