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Editorial Team
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Asked: 2026-06-15T22:29:51+00:00

TLDR : I’m using a variable of type void * to hold a string

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TLDR: I’m using a variable of type void * to hold a string pointer, how do I modify the value of the string?

BACKGROUND
Homework assignment with IPC has arisen.
I have two processes, chefs and waiters where the waiters give some input to the chefs (party seated, table orders, ready to check out etc.), and then the chef sends the information back to the relevant waiter (obviously not all waiters are serving all the tables at the same time).

My (admittedly clunky) solution:
1. Chef opens ‘chef’ FIFO file to read

2. Waiter opens ‘chef’ to write and writes the name of the waiter, and opens a FIFO with that name to read.

3. Chef reads name of the waiter and opens the FIFO to write.

3.a. (Not really relevant to the issue I’m having) Waiter sends input through ‘chef’, until the chef closes down the system.

4. During the waiters input, occasionally the chef will have to send information back. When the chef enters output, a check occurs to determine which output FIFO to write to.

QUESTION
I have two pthreads, and need to send a string back. I have passed a string pointer as the one parameter I’m given, (in this case called void *arg), then when I need to send some information back, I’m trying to just put the string in in the pointer I passed but have yet to find anyway to do that. So my question is, how might I do it this way?

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1 Answer

  1. Editorial Team

    I wound up utilizing the following:

    string* temp = static_cast<string*>(arg);

    Then modified just modified temp. Since arg held the location of the string back in the main thread, temp took it and then I could put the string in temp. Inter-thread communication was thus established, and I was able to continue implementing my terrible design.

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