Berkeley CSUA MOTD:Entry 54763
Berkeley CSUA MOTD
2014/1/14-2/5 [Computer/SW/Languages/C_Cplusplus] UID:54763 Activity:nil
1/14    Why is NULL defined to be "0" in C++ instead of "((void *) 0)" like in
        C?  I have some overloaded functtions where one takes an integer
        parameter and the other a pointer parameter.  When I call it with
        "NULL", the compiler matches it with the integer version instead of
        the pointer version which is a problem.  Other funny effect is that
        sizeof(NULL) is different from sizeof(myPtr).  Thanks.
        \_ In C, a void pointer is implicitly convertable to any other pointer
           type, so (void *)0 works in any context where you need a pointer.
           C++ doesn't allow that conversion, because it isn't typesafe.
           (That's why you can write "int *p = malloc(4)" in C but not in C++.)
           Unfortunately, there's no simple equivalent of (void *)0 that works
           in C++.  Recent C++ compilers have added a new keyword "nullptr"
           that does the right thing, but they've avoided defining NULL to it
           so they don't break old code.  --mconst
2017/08/21 [General] UID:1000 Activity:popular

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2013/4/9-5/18 [Computer/SW/Languages/C_Cplusplus, Computer/SW/Apps, Computer/SW/Languages/Perl] UID:54650 Activity:nil
4/04    Is there a good way to diff 2 files that consist of columns of
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        \_ Use Excel.
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2012/7/19-11/7 [Computer/SW/Languages/C_Cplusplus] UID:54439 Activity:nil
7/19    In C or C++, how do I write the code of a function with variable
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        \_ The usual way (works on gcc 3.0+, Visual Studio 2005+):
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2011/3/7-4/20 [Computer/SW/Languages/C_Cplusplus] UID:54056 Activity:nil
3/7     I have a C question.  I have the following source code in two identical
        files t.c and t.cpp:
                #include <stdlib.h>
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2011/2/5-19 [Computer/SW/Languages/C_Cplusplus] UID:54027 Activity:nil
2/4     random C programming/linker fu question.  If I have
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        \_ I don't pretend to actually know the right answer to this, but
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2/12    I need a way to make a really big C++ executable (~200MBs) that does
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        \_ static link in lots of libraries?
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2009/9/28-10/8 [Computer/SW/Languages/C_Cplusplus] UID:53409 Activity:nil
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        C#, Python, Javascript, then finally Ruby. The good news is
        Pascal is going waaaay back up!
        \_ C is still more popular than C++?  I feel much better about myself
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8/6     In C one can do "typedef int my_index_t;".  What's the equivalent in
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        \_ C#? Are you serious? Is this what the class of 2009 learn?
           \_ No.  I have to learn .NET code at work.  I am Class of '93.
           \_ python is what 2009 learns, see the motd thread about recent
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7/20    For those who care btw, it looks like eclipse is now A Standard Tool
        at UCB ugrad cs, probably replaced emacs.  Furthermore, people get
        angry at seeing Makefiles, (since eclispe takes care of that).  I
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        \_ The more people at my work use eclipse the less the code is
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