FIDO_DEV_GET_TOUCH_BEGIN(3)                           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.

Linux 6.7.4-arch1-1             August 5, 2020             Linux 6.7.4-arch1-1