Hi, In response to the message, I had asked for the retrieval of the option val= ues:
void PopulateScannerData(SANE_Handle handle) { =09int index; =09unsigned long value;=09 =09SANE_Status status; =09const SANE_Option_Descriptor* options=3DNULL; =09if(IsSupported(gData,SANE_NAME_SCAN_X_RESOLUTION,&index)) =09{ =09=09status =3D sane_control_option(handle,index,SANE_ACTION_GET_VALUE,(vo= id*)value,0); =09=09assert(status =3D=3D SANE_STATUS_GOOD); =09=09CSane::x_resolution =3D value; =09} =09if(IsSupported(gData,SANE_NAME_SCAN_Y_RESOLUTION,&index)) =09{ =09=09status =3D sane_control_option(handle,index,SANE_ACTION_GET_VALUE,(vo= id*)value,0); =09=09assert(status =3D=3D SANE_STATUS_GOOD); =09=09CSane::y_resolution =3D value; =09} =09else =09=09CSane::y_resolution =3D CSane::x_resolution; } I receive a SIGSEGV in this code. The gdb trace is : #0 0x465cfaf0 in sanei_hp_accessor_new () from /usr/lib/sane/libsane-hp.so= .1 #1 0x465cf903 in sanei_hp_accessor_get () from /usr/lib/sane/libsane-hp.so= .1 #2 0x465d32f6 in sanei_hp_choice_isEnabled () from /usr/lib/sane/libsane-hp.so.1 #3 0x465d8c27 in sanei_hp_optset_control () from /usr/lib/sane/libsane-hp.= so.1 #4 0x465d1ed5 in sanei_hp_handle_control () from /usr/lib/sane/libsane-hp.= so.1 #5 0x465ca534 in sane_hp_control_option () from /usr/lib/sane/libsane-hp.s= o.1 #6 0x41eacc2a in sane_dll_control_option () from /usr/lib/libsane.so.1 #7 0x41eacf7b in sane_control_option () from /usr/lib/libsane.so.1 #8 0x41fb358a in PopulateScannerData(void*)..... Can any one tell me what am I doing wrong? Thanks, Mohit Message: 5 Date: Wed, 22 Jun 2005 18:06:25 +0200 From: Henning Meier-Geinitz <henn...@meier-geinitz.de> To: sane-devel@lists.alioth.debian.org Subject: Re: [sane-devel] Determining the "SET" values of options through SANE APIs Hi, On Wed, Jun 22, 2005 at 07:17:19PM +0530, Mohit Kumar wrote: > I was wondering if there is any mechanism for which I can find out > what are the set values for various options such as resolution, mode > etc? > > sane_get_option_descriptor gives us all the options, but is there any > way to determine what is the current value of the option? sane_control_option(), SANE_ACTION_GET_VALUE Bye, Henning