rec@dg.dg.com (Robert Cousins) (06/20/89)
I have found that there are several basic bugs in the Cshell history mechanism which can be quite problematic. These were originally called to my attention by the work of a couple of researchers at the U of W in Madison. Bug 1: !a%999999999f which causes 999999999 spaces to be output to the screen. (Fewer on 16 bit machines.) It seems that the error message in the history module goes through the first argument of a printf() call and can be interpreted as a format. A second bug, which happens on fewer machines takes place with: !a%f%f which can cause csh to dump core from a floating point error. Comments? I've tried this on almost every machine I can get my hands on and the first bug is definitely there on everyone. For a reasonable variation, try differing format specifications. Use of fractional and negative field widths can bring about interesting outputs! Robert Cousins Dept. Mgr, Workstation Dev't. Data General Corp. Speaking for myself alone.