This prevents converting "+3" into "-k4.1" in places where getopt
won't recognize it, which in turn prevents silly error messages and
lossage trying to sort files whose names begin with +. PR 43358.
This frees a byte value to use for 'end of key' (to correctly sort
short keys) while still having a weight assigned to the field sep.
(Unless -t is given, the field sep is in the field data.)
Do reverse sorts by writing the output file in reverse order (rather
than reversing the sort - apart from merges).
All key compares are now unweighted.
For 'sort -u' mark duplicates keys during the sort and don't write
to the output.
Use -S to mean a posix sort - where equal keys are sorted using the
raw record (rather than being kept in the original order).
For 'sort -f' (no keys) generate a key of the folded data (as for -n
-i and -d), simplifies the code and allows a 'posix' sort.
Currently unchanged apart from the deletion of the 'unstable' version and
other unneeded code.
Use fldtab[0]. not fldtab-> when we are referring to the global info
in the 0th entry to emphasise that this entry is different.
fldtab[0].weights is only needed in the SINGL_FLD case - so set it there.
Re-indent a big 'if' is setfield() so that the line breaks match the
logic - which looks dubious now!
as if part of the data.
This is a bit fubar since we need a value than sorts before any byte value
as a key field separator - so need 257 byte values (since radixsort() doesn't
take a length for each record).
For now map '\t' to 0x01 and hope no one will notice!
- If we generate a key, it is always sortable using memcmp()
- If we are sorting the whole record, then a weight-table must be used
during compares.
- Major surgery to encoding of numbers to ensure unique keys for equal
numeric values. Reverse numerics are handled by inverting the sign.
- Case folding (-f) is handled when the sort keys are generated. No other
code has to care at all.
- Key uniqueness (-u) is done during merge for large datasets. It only
has to be done when writing the output file for small files.
Since the file is in key order this is simple!
Probably fixes all of: PR/27257 PR/25551 PR/22182 PR/31095 PR/30504
PR/36816 PR/37860 PR/39308
Also PR/18614 should no longer die, but a little more work needs to be
done on the merging for very large files.
foo += sscanf(++foo, ...);
constructs to:
++foo;
foo += sscanf(foo, ...);
to avoid the following warning from gcc 3.1:
warning: operation on `pos' may be undefined
