madden (11/25/82)
As distributed, the 4.1BSD pascal compiler (pc) will destroy or
completely remove the file associated with a source argument name
longer that 14 characters. If the long argument ends with ".p", the
compiler generates the corresponding object file name by replacing the
"p" with an "o" without attention to the fact that the file system
entry for the two names will be the same. The result is immediate
disaster.
We have some naive students here who have been burned by the
scenario:
ex program3.source.p
.
.
.
wq
pc program3.source.p
This sequence generates no complaints from ex or pc, even though
the file name actually created is "program3.sourc"; unfortunately,
after a successful compile, a.out exists but "program3.sourc" has
disappeared.
As an expedient solution, I have patched /usr/src/cmd/pascal/pc.c to
generate a complaint and quit as shown by the diff at the end of this
note.
Jim Madden
UCSD Computer Center
ucbvax!sdcsvax!madden
------- pc.c -------
*** /tmp/d23229 Thu Nov 25 02:21:21 1982
--- pc.c Wed Nov 24 18:52:05 1982
***************
*** 185,190
savargx = pc0argx;
for (i = 0; i < argc; i++) {
argp = argv[i];
if (argp[0] == '-')
continue;
if (suffix(argp) == 's') {
--- 185,196 -----
savargx = pc0argx;
for (i = 0; i < argc; i++) {
argp = argv[i];
+ if (strlen(argp)>14) {
+ fprintf(stderr,
+ "pc: file names must be <= 14 characters long (%s)\n"
+ ,argv[i]);
+ exit(1);
+ }
if (argp[0] == '-')
continue;
if (suffix(argp) == 's') {