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FIDO_DEV_GET_TOUCH_BEGIN(3) FreeBSD Library Functions Manual
NAME
fido_dev_get_touch_begin, fido_dev_get_touch_status - asynchronously wait
for touch on a FIDO2 authenticator
SYNOPSIS
#include <fido.h>
int
fido_dev_get_touch_begin(fido_dev_t *dev);
int
fido_dev_get_touch_status(fido_dev_t *dev, int *touched, int ms);
DESCRIPTION
The functions described in this page allow an application to
asynchronously wait for touch on a FIDO2 authenticator. This is useful
when multiple authenticators are present and the application needs to
know which one to use.
The fido_dev_get_touch_begin() function initiates a touch request on dev.
The fido_dev_get_touch_status() function continues an ongoing touch
request on dev, blocking up to ms milliseconds. On success, touched will
be updated to reflect the touch request status. If touched is 1, the
device was touched, and the touch request is terminated. If touched is
0, the application may call fido_dev_get_touch_status() to continue the
touch request, or fido_dev_cancel() to terminate it.
RETURN VALUES
The error codes returned by fido_dev_get_touch_begin() and
fido_dev_get_touch_status() are defined in <fido/err.h>. On success,
FIDO_OK is returned.
EXAMPLES
Please refer to examples/select.c in libfido2's source tree.
SEE ALSO
fido_dev_cancel(3)
CAVEATS
The fido_dev_get_touch_status() function will cause a command to be
transmitted to U2F authenticators. These transmissions should not exceed
a frequency of 5Hz.
FreeBSD 14.0-RELEASE-p11 August 5, 2020 FreeBSD 14.0-RELEASE-p11