+--- cpmtools-2.15/device_libdsk.c.orig 2012-03-18 19:18:16.000000000 +0100
++++ cpmtools-2.15/device_libdsk.c 2013-03-02 21:24:38.201841462 +0100
+@@ -31,7 +31,7 @@
+ this->sectrk=sectrk;
+ this->tracks=tracks;
+ /* Must be an even multiple of sector size */
+- assert((offset%secLength==0);
++ assert(offset%secLength==0);
+ this->offset=offset;
+
+ this->geom.dg_secsize = secLength;
+@@ -65,7 +65,7 @@
+ const char *Device_readSector(const struct Device *this, int track, int sector, char *buf)
+ {
+ dsk_err_t e;
+- e = dsk_lread(this->dev, &this->geom, buf, (track * this->sectrk) + sector + offset/this->secLength);
++ e = dsk_lread(this->dev, &this->geom, buf, (track * this->sectrk) + sector + this->offset/this->secLength);
+ return (e?dsk_strerror(e):(const char*)0);
+ }
+ /*}}}*/
+@@ -73,7 +73,7 @@
+ const char *Device_writeSector(const struct Device *this, int track, int sector, const char *buf)
+ {
+ dsk_err_t e;
+- e = dsk_lwrite(this->dev, &this->geom, buf, (track * this->sectrk) + sector + offset/this->secLength);
++ e = dsk_lwrite(this->dev, &this->geom, buf, (track * this->sectrk) + sector + this->offset/this->secLength);
+ return (e?dsk_strerror(e):(const char*)0);
+ }
+ /*}}}*/