c++ - Linux, share a buffer with another program in fork() -

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i have client/server model each client can send task server - called task requesting.

this base simple distributed-computing library after.

"in other words, if ordinary application processes array of independent elements, in data-parallel model, each processor assigned process part of array. support data-parallel computing, core library should divide tasks parts, transfer task data local memory of particular cpu, run task on cpu, transfer results caller, , provide ability request global data caller."

data paraller diagram

  • a task binary(std::vector uint8_t) , payload(std::vector uint8_t).
  • a binary compiled task / application.
  • a payload optional data serialized uint8_t.

so simply:

class cgridtask {      public:         ...          bool        run             ();          private:         std::vector<uint8_t>        m_vbinary;         std::vector<uint8_t>        m_vpayload;         uint32_t                    m_uiuniqueid;          ... }

the pseudo-diagram shows how 'works':

[client1]---[send task payload: integer value = 10]-->[server]  [server]-->[run task payload]  [task, start]  [task, calculate...] [task, calculate...] [task, calculate...] [task, integer value = 10 + new value]  [task, return]  [server]-->[send task client1]

ok, when server calls:

pgridtask->run();

here should happen:

bool cgridtask::run() {     // dump binary temporary file     dump(m_vbinary);      // chmod +x     system("chmod +x " + strtempoprarybinaryname);      // run binary , pass m_vpayload     ...how can this?...      // return true if binary executed     return true; }

the problem here share m_vpayload executed binary... how can this?

thank input this!

as alternative other solutions, , depending on how child process structured, communicate child process through pipes (the usual pipe/fork/dup2/exec pattern).

sure performance worse shared memory, whole architecture more flexible, , various programs less coupled: child's point of view, takes data stdin , outputs results stdout makes reusable in other contexts (and makes easy reuse "ordinary" interactive programs in context of task server without having adapt them first).


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