As far as I know the old behavior was unintended and incorrect, and the
current behavior is correct.
Terrence Doyle
On 5/22/15 7:10 AM, lijo george wrote:
> Thanks for the clarifcation. So can I assume that the earlier behaviour
> was somehow unintended
> and the current behaviour is the right one. i.e the syntax error thrown
> is valid.
>
> The reason I'm asking is there are some old scripts with this syntax
> which used to work in ksh2011,
> so if this is not a bug, I guess I'll need to fix those scripts rather
> than waiting for ksh to be fixed.
>
> On Tue, May 19, 2015 at 9:35 PM, Terrence J. Doyle
> <terrence.j.doyle+...@gmail.com <mailto:terrence.j.doyle+...@gmail.com>>
> wrote:
>
>
> Actually, I'm surprised this ever worked. The quotes on line
> 5 of your
> script should be escaped, like this:
>
> FS = \"[()]\"
>
> Without the escapes ksh matches the double-quote after A= with the first
> one on line 5. So, the characters, [()], are unquoted (in both ksh and
> awk). Then, quoting is re-initiated with the second double-quote on
> line 5.
>
> However, I did try your script with ksh version: Version M
> 1993-12-28
> s+. It did indeed succeed without the escaped double-quotes. Then, I
> reran the script with line 5 modified like this:
>
> FS = "()"
>
> With that the older version of ksh failed with the error:
>
> line 2: syntax error at line 5: `(' unexpected
>
> With line 5 modified as:
>
> FS = \"()\"
>
> The script once again succeeded (albeit with a different answer because
> awk's FS had a different value).
>
> These variations seem to indicate that in older versions of
> ksh square
> brackets could be used as a quasi-quoting mechanism. But, as far as I
> know this /feature/ was not documented and should not have been
> relied-upon. Escaping the double-quotes on line 5 is the way to go.
>
> Terrence Doyle
>
> On 5/17/15 4:23 PM, lijo george wrote:
> > I observed a syntax error with a script in ksh versions starting from
> > 2012-08-01.
> > A minimal test case is given below.
> > Basically if the pattern "[()]" is used as field separator in awk, it
> > throws a syntax error.
> >
> > # ksh --version
> > version sh (AT&T Research) 93u+ 2012-08-01
> > # cat test-simple.ksh
> > NAWK=/usr/bin/nawk
> > TEST="abc(def)g)"
> > A="`echo $TEST | $NAWK '
> > BEGIN{
> > FS = "[()]"
> > }
> > /^a/ {
> > print $1
> > }
> > END{
> > #print $2
> > }'`"
> > print $A
> > # ksh test-simple.ksh
> > test-simple.ksh: line 2: syntax error at line 5: `(' unexpected
> >
> >
> > This used to work in the 2011-02-08 version.
> > Is this a bug or expected behaviour.
> >
> > From the sh_lex function in the lex.c file, I can see that there is a
> > check added for the pattern "[(" given below.
> > case S_EPAT:
> > epat:
> > if(fcgetc(n)==LPAREN && c!='[')
> >
> > But in the earlier version(2011-02-08), the corresponding check was
> >
> > case S_EPAT:
> > epat:
> > if(fcgetc(n)==LPAREN)
> >
> >
> > So I guess the extra check was added for some specific reason. In that
> > case, could someone please let me know the reason why this was
> added and
> > the syntax error is thrown.
> >
> > Thanks,
> > Lijo
> >
> >
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