incremental updating was broken since version 4.2

[Hideki IWAMOTO]

You permitted duplicate keys in GPATH by following change.
  
http://savannah.gnu.org/cgi-bin/viewcvs/global/global/libutil/gpathop.c.diff?r1=1.6&r2=1.7
  
http://savannah.gnu.org/cgi-bin/viewcvs/global/global/libutil/gtagsop.c.diff?r1=1.14&r2=1.15
As the result, "gtags -i" came to add NEXTKEY instead of replacing NEXTKEY.
This is wrong behavior.
May I return the specification of gpath_open before version 4.2
by deleting the 3rd argument of gpath_open?

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This is an example.

$ touch foo.c
$ gtags
$ global -P
foo.c
$ mv foo.c bar.c
$ gtags -i
$ global -P
bar.c
$ mv bar.c foo.c
$ gtags -i
$ global -P
foo.c
$ mv foo.c bar.c
$ gtags -i
$ global -P
bar.c
foo.c
$ global -Po
bar.c
$ db_dump185 -p GPATH | awk '{if(body){if(key){printf("%-20s 
%s\n",key,$0);key="";}else key=$0;}else{if($0=="HEADER=END")body=1;}}'
 __.NEXTKEY\00       2\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       2\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       4\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       4\00
 __.NEXTKEY\00       4\00
 __.NEXTKEY\00       4\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       3\00
 __.NEXTKEY\00       2\00
./bar.c\00           3\00
./foo.c\00           3\00
3\00                 ./bar.c\00
3\00                 ./foo.c\00


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Hideki IWAMOTO  address@hidden