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How to define a variable compatible with npos in C++

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Rich:
Hi Paul_123
I did decide to test this for myself by adding  lst=onboot.lst  to the end of  cmdline.
Result:
eloc  was set to 4294967295
work  was set to 4294967226
onbootName  was correctly set to  onboot.lst  and no seg fault occurred.

Since a trailing space or end of string marker (\0) are both
acceptable in this case, it works correctly because C++
hid the error (or failed gracefully).

Thank you for the explanation.

Paul_123:
Was playing with Copilot in github today.

Prompt:  write code in c++ to parse the linux kernel command line


--- Code: ---#include <iostream>
#include <fstream>
#include <sstream>
#include <map>
#include <string>

int main() {
    const std::string cmdlinePath = "/proc/cmdline";
    std::ifstream cmdlineFile(cmdlinePath);

    if (!cmdlineFile.is_open()) {
        std::cerr << "Error: Could not open " << cmdlinePath << std::endl;
        return 1;
    }

    std::string cmdline;
    std::getline(cmdlineFile, cmdline);
    cmdlineFile.close();

    std::map<std::string, std::string> cmdlineParams;
    std::istringstream stream(cmdline);
    std::string token;

    while (std::getline(stream, token, ' ')) {
        size_t equalPos = token.find('=');
        if (equalPos != std::string::npos) {
            std::string key = token.substr(0, equalPos);
            std::string value = token.substr(equalPos + 1);
            cmdlineParams[key] = value;
        } else {
            cmdlineParams[token] = ""; // Parameter without a value
        }
    }

    // Display the parsed parameters
    std::cout << "Parsed Kernel Command Line Parameters:" << std::endl;
    for (const auto& param : cmdlineParams) {
        std::cout << param.first << " = " << (param.second.empty() ? "(no value)" : param.second) << std::endl;
    }

    return 0;
}

--- End code ---

Not drastically different than what we are doing.   Copilot always used size_t for the result coming from find.

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