itojun@iijlab.net writes:
> 
> >[Sorry, more traffic] In fact, I've just discovered the
> >problem... it crashes when it has no data to sort (first
> >character it reads is EOF).  I'll [maybe fix and] send-pr.
> 
> 	I guess that problem was solved by usr.bin/sort/fsort.c,
> 	revision 1.12.  please try the latest code.

[I was running 1.12] ... ah, I see.  This error now only
occurs for filter mode

  touch /tmp/emptyfile
  cat emptyfile | sort -f

Stace trace follows.

Mark <><

-- snip --

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This GDB was configured as "i386--netbsd"...
Core was generated by `sort'.
Program terminated with signal 10, Bus error.
Reading symbols from /usr/libexec/ld.elf_so...done.
Reading symbols from /usr/lib/libc.so.12...done.
#0  0x804a341 in putline (rec=0xfffffff8, fp=0x480fd300)
    at /usr/src/usr.bin/sort/files.c:332
332             EWRITE(rec->data+rec->offset, 1, rec->length - rec->offset, fp);
(gdb) where
#0  0x804a341 in putline (rec=0xfffffff8, fp=0x480fd300)
    at /usr/src/usr.bin/sort/files.c:332
#1  0x80492e6 in append (keylist=0x8064000, nelem=0, depth=8, fp=0x480fd300, 
    put=0x804a338 <putline>, ftbl=0xbfbfd1f4)
    at /usr/src/usr.bin/sort/append.c:131
#2  0x804a9db in fsort (binno=-1, depth=0, top=0, filelist=0xbfbfd1f0, 
    nfiles=1, outfp=0x480fd300, ftbl=0xbfbfd1f4)
    at /usr/src/usr.bin/sort/fsort.c:212
#3  0x804ca54 in main (argc=3, argv=0xbfbfd3ec)
    at /usr/src/usr.bin/sort/sort.c:268
#4  0x8048d49 in ___start ()
(gdb)