chad@lakesys.UUCP (D. Chadwick Gibbons) (02/12/89)
I am in need of a version of memcpy() that handles alignment restrictions within pointers. The few versions of source that I have work well, except they do not allow you to preform an operation such as: char *dst; struct magic *src; memcpy(dst, src, sizeof(src)); The pointer alignment for the structure does not coincide with that of the character pointer, and thus the function bombs. Why not use the standard library version? I am running under XENIX and need to use a far pointer in a small model program...as you know, you have to write your own versions of the standard library routines in this situation. I need to be able to have *dst be a char far *dst, instead of the normal near pointer. I appreciate any information, of course. -- D. Chadwick Gibbons, chad@lakesys.lakesys.com, ...!uunet!marque!lakesys!chad
manning@nntp-server.caltech.edu (Evan Marshall Manning) (11/13/90)
The title about says it. I need to move data from point A to point B, where there may be a bit offset as well as a byte offset. Is there any reasonably portable and/or reasonably fast way to do this? If it matters, I'm using a 68030 with a (buggy) "Classic C" compiler under PDOS. Yes, I know this is a silly thing to do. I'm lobbying to restart on bit slips, but nobody asks me. Thanks, -- Evan *************************************************************************** Your eyes are weary from staring at the CRT for so | Evan M. Manning long. You feel sleepy. Notice how restful it is | is to watch the cursor blink. Close your eyes. The |manning@gap.cco.caltech.edu opinions stated above are yours. You cannot | manning@mars.jpl.nasa.gov imagine why you ever felt otherwise. | gleeper@tybalt.caltech.edu
gwyn@smoke.brl.mil (Doug Gwyn) (11/13/90)
In article <1990Nov12.235038.16331@nntp-server.caltech.edu> manning@nntp-server.caltech.edu (Evan Marshall Manning) writes: >The title about says it. I need to move data from point A to >point B, where there may be a bit offset as well as a byte offset. >Is there any reasonably portable and/or reasonably fast way to do >this? This is known as a "bit blit" (special case of "rasterop"), and algorithms are described in the computer graphics literature. For example, there was an article in "Software -- Practice and Experience" by Locanthi and Pike on the method used in the Blit terminal.