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Full Discussion: FIFO possible blocking or unknown error
Homework and Emergencies Homework & Coursework Questions FIFO possible blocking or unknown error Post 302444780 by Corona688 on Thursday 12th of August 2010 07:04:27 PM
Old 08-12-2010
Code:
...
    #undef FIFOSERVER
    #undef FIFOCLIENT
    #define FIFOSERVER fifoNames[1]
    #define FIFOCLIENT fifoNames[2]

#define's are, more or less, literal text replacement operators that happen even before the program is compiled.

For example:

Code:
#define A  FUNCTION_A

A();

void function_c()
{
        A();
}

#undef A
#define A FUNCTION_B
A();

function_c();

When you compile it, the first step it does is preprocessing, which does the text replacement, reducing the code to this:

Code:
FUNCTION_A();

void function_c()
{
        A();
}

FUNCTION_B();

function_c();

meaning function_c calls FUNCTION_A, not FUNCTION_B. So, this text replacement cannot do any logic at runtime. All decisions it makes happen right when the code is compiled. If you want to change what files your function opens, pass it parameters so you can tell it so:
Code:
void chatty(const char *rdfile, const char *wrfile)
{
        ...
}

...


chatty(fifonames[0], fifonames[1]);

...

chatty(fifonames[1], fifonames[0]);

 

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LEARN ABOUT DEBIAN

std::hash

std::hash< _Tp >(3cxx)													    std::hash< _Tp >(3cxx)

NAME

       std::hash< _Tp > -

SYNOPSIS

       Inherits std::__hash_base< _Result, _Arg >.

   Public Types
       typedef _Arg argument_type
       typedef _Result result_type

   Public Member Functions
       size_t operator() (_Tp __val) const
       template<> size_t operator() (bool __val) const
       template<> size_t operator() (char __val) const
       template<> size_t operator() (signed char __val) const
       template<> size_t operator() (unsigned char __val) const
       template<> size_t operator() (wchar_t __val) const
       template<> size_t operator() (char16_t __val) const
       template<> size_t operator() (char32_t __val) const
       template<> size_t operator() (short __val) const
       template<> size_t operator() (int __val) const
       template<> size_t operator() (long __val) const
       template<> size_t operator() (long long __val) const
       template<> size_t operator() (unsigned short __val) const
       template<> size_t operator() (unsigned int __val) const
       template<> size_t operator() (unsigned long __val) const
       template<> size_t operator() (unsigned long long __val) const
       template<> size_t operator() (float __val) const
       template<> size_t operator() (double __val) const
       template<> size_t operator() (long double __val) const

Detailed Description
   template<typename _Tp>struct std::hash< _Tp >
       Primary class template hash.

       Definition at line 58 of file functional_hash.h.

Author
       Generated automatically by Doxygen for libstdc++ from the source code.

libstdc++							  Tue Nov 27 2012					    std::hash< _Tp >(3cxx)
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