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revision 690 by ph10, Wed Nov 24 17:39:25 2010 UTC revision 691 by ph10, Sun Sep 11 14:31:21 2011 UTC
# Line 28  instead of having to compile them every Line 28  instead of having to compile them every
28  If you are not using any private character tables (see the  If you are not using any private character tables (see the
29  <a href="pcre_maketables.html"><b>pcre_maketables()</b></a>  <a href="pcre_maketables.html"><b>pcre_maketables()</b></a>
30  documentation), this is relatively straightforward. If you are using private  documentation), this is relatively straightforward. If you are using private
31  tables, it is a little bit more complicated.  tables, it is a little bit more complicated. However, if you are using the
32    just-in-time optimization feature of <b>pcre_study()</b>, it is not possible to
33    save and reload the JIT data.
34  </P>  </P>
35  <P>  <P>
36  If you save compiled patterns to a file, you can copy them to a different host  If you save compiled patterns to a file, you can copy them to a different host
# Line 36  and run them there. This works even if t Line 38  and run them there. This works even if t
38  to the one on which the patterns were compiled. There may be a small  to the one on which the patterns were compiled. There may be a small
39  performance penalty, but it should be insignificant. However, compiling regular  performance penalty, but it should be insignificant. However, compiling regular
40  expressions with one version of PCRE for use with a different version is not  expressions with one version of PCRE for use with a different version is not
41  guaranteed to work and may cause crashes.  guaranteed to work and may cause crashes, and saving and restoring a compiled
42    pattern loses any JIT optimization data.
43  </P>  </P>
44  <br><a name="SEC2" href="#TOC1">SAVING A COMPILED PATTERN</a><br>  <br><a name="SEC2" href="#TOC1">SAVING A COMPILED PATTERN</a><br>
45  <P>  <P>
# Line 76  some daemon process that passes them via Line 79  some daemon process that passes them via
79  them.  them.
80  </P>  </P>
81  <P>  <P>
82  If the pattern has been studied, it is also possible to save the study data in  If the pattern has been studied, it is also possible to save the normal study
83  a similar way to the compiled pattern itself. When studying generates  data in a similar way to the compiled pattern itself. However, if the
84  additional information, <b>pcre_study()</b> returns a pointer to a  PCRE_STUDY_JIT_COMPILE was used, the just-in-time data that is created cannot
85    be saved because it is too dependent on the current environment. When studying
86    generates additional information, <b>pcre_study()</b> returns a pointer to a
87  <b>pcre_extra</b> data block. Its format is defined in the  <b>pcre_extra</b> data block. Its format is defined in the
88  <a href="pcreapi.html#extradata">section on matching a pattern</a>  <a href="pcreapi.html#extradata">section on matching a pattern</a>
89  in the  in the
# Line 120  If you saved study data with the compile Line 125  If you saved study data with the compile
125  reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in the  reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in the
126  <i>flags</i> field to indicate that study data is present. Then pass the  <i>flags</i> field to indicate that study data is present. Then pass the
127  <b>pcre_extra</b> block to <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b> in the  <b>pcre_extra</b> block to <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b> in the
128  usual way.  usual way. If the pattern was studied for just-in-time optimization, that data
129    cannot be saved, and so is lost by a save/restore cycle.
130  </P>  </P>
131  <br><a name="SEC4" href="#TOC1">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a><br>  <br><a name="SEC4" href="#TOC1">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a><br>
132  <P>  <P>
# Line 138  Cambridge CB2 3QH, England. Line 144  Cambridge CB2 3QH, England.
144  </P>  </P>
145  <br><a name="SEC6" href="#TOC1">REVISION</a><br>  <br><a name="SEC6" href="#TOC1">REVISION</a><br>
146  <P>  <P>
147  Last updated: 17 November 2010  Last updated: 26 August 2011
148  <br>  <br>
149  Copyright &copy; 1997-2010 University of Cambridge.  Copyright &copy; 1997-2011 University of Cambridge.
150  <br>  <br>
151  <p>  <p>
152  Return to the <a href="index.html">PCRE index page</a>.  Return to the <a href="index.html">PCRE index page</a>.
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