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copied!<p>Using regexes is not reliable, doubly not with egrep, unless you follow some conventions and don't do anything too hard.</p> <p>Consider:</p> <pre><code>void * function( int a, void (*pointer)(const char *, int, double), double d ) </code></pre> <p>This declaration is spread over 6 lines - and egrep only looks at one line at a time.</p> <p>This declaration contains 5 commas and 3 parameters.</p> <p>If you put enough restrictions on the code you are searching, you can probably get an approximation to what you are after, but C and C++ are both very hard to analyze. And I'm not even thinking about macros that invoke the function for you.</p> <hr> <p>Your proposed solution has a number of flaws, even after solving the problem with the extraneous backslashes (diagnosed correctly by Tim Pietzcker):</p> <pre><code>egrep "find" * | egrep "\([^,]*,[^,]*,[^,]*\)" </code></pre> <p>This will discover lines such as:</p> <pre><code>find(1, 2, 3); int extra_find(int a, int b, int c) { ... } extraordinary(find, 3, 21); printf("find: %.*s\n", 13, "heliotrope"); for (find(1); printf("%d %d\n", 1, 2); x++) for (x(find, 1); b < max(c, d); i++) /* find(1,2,3) */ </code></pre> <p>Only one of those is a function definition, and that still isn't one of the outputs you wanted.</p> <p>If you can play with Perl (or Python) or any tool with PCRE (Perl-Compatible Regular Expressions) or equivalent, then you can do things like ensure that on a single line the word 'find' appears followed by an open parenthesis, a sequence of 'type name' values separated by commas and white space, and a close parenthesis.</p> <pre><code>perl -ne 'print if m/\bfind\s*\(\w+\s+\w+(\s*,\s*\w+\s+\w+){2}\s*\)/' </code></pre> <p>But that doesn't handle pointers, arrays, qualifiers like 'const', or pointers to functions (or references, if you are using C++), or structures referenced by 'struct somename varname', or function definitions protected against macro expansion (<code>int (getchar)(int c)</code>), or ... And it still doesn't distinguish between declarations and definitions!</p>

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