how to make parser thread safe ?

[arun kv]

  Hi,
 
To make parser thread safe,  should i just declare a variable in my yacc file 
like this %pure-parser (as seen in the second line of my code given below)
 
will it do everything to make my parser thread safe . should i use other locks 
and all in my code.
 
what else should i take care along along with declaring %pure-parser to make my 
parser thread safe.
 
i am a beginner in the field of lex and yacc ..
please do help me....
 
expecting a reply ....
 
thanks in advance 
Arun
 
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%name Parser
 
%pure-parser
%header{

#define YYDEBUG      1
#define YYPRINTF     1
#define YYMAXDEPTH   600000
#define YYINITDEPTH  5000
#define YYSTYPE  char *

%}

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