clipboard.txt

watch cat /proc/$(ps a|grep xiinux|head -n1|awk '{print $1}')/status

cppcheck --enable=all src/main.cpp


# watch open sockets count
XID=$(ps a|grep xiinux|head -n1|awk '{print $1}') watch -n 1 "lsof -a -p $XID -i | grep TCP | wc -l"

TAG=$(date "+%Y-%m-%d--%H-%M") && git tag $TAG && git push origin $TAG

git reset --hard HEAD

ulimit -n
ulimit -n 4000

./test-coverage.sh | tee test-coverage.log

# coverage
llvm-profdata merge -sparse default.profraw -o default.profdata
llvm-cov export --format=lcov --instr-profile default.profdata --object xiinux > lcov.info
llvm-cov show xiinux -instr-profile=default.profdata

sudo tcpdump -A -i lo -n port 8088

sudo sysctl net.ipv4.ip_local_port_range='1024 65000'
sudo sysctl net.core.somaxconn=40000

# to allow more concurrent connections
sudo sysctl fs.file-max=70000

# allow connection flood
sudo sh -c "echo 0 >/proc/sys/net/ipv4/tcp_syncookies"
sudo sh -c 'echo 30000>/proc/sys/net/ipv4/tcp_max_syn_backlog'

# recycles connections after 5 seconds of wait mode
sudo sysctl net.ipv4.tcp_tw_reuse=1
sudo sysctl net.ipv4.tcp_fin_timeout=5

# increase maximum number of open files (relogin)
#vi /etc/security/limits.conf
#c                soft    nofile          20000
#c                hard    nofile          40000

hey -n 10000 -c 1 http://localhost:8088/qa/files/far_side_dog_ok.jpg


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// Create epoll instance
int epoll_fd = epoll_create1(0);

// Add socket to epoll
struct epoll_event event;
event.events = EPOLLIN;
event.data.fd = socket_fd;
epoll_ctl(epoll_fd, EPOLL_CTL_ADD, socket_fd, &event);

// Create timer file descriptor
int timer_fd = timerfd_create(CLOCK_MONOTONIC, 0);

// Add timer to epoll
event.events = EPOLLIN;
event.data.fd = timer_fd;
epoll_ctl(epoll_fd, EPOLL_CTL_ADD, timer_fd, &event);

// Main event loop
while (true) {
    struct epoll_event events[2];
    int num_events = epoll_wait(epoll_fd, events, 2, -1);

    for (int i = 0; i < num_events; ++i) {
        int fd = events[i].data.fd;

        if (fd == socket_fd) {
            // Handle socket event
            // Process incoming data

            // Reset the timer when there is activity on the socket
            struct itimerspec timer_spec;
            timer_spec.it_value.tv_sec = 60;  // 1 minute
            timer_spec.it_value.tv_nsec = 0;
            timer_spec.it_interval.tv_sec = 0;
            timer_spec.it_interval.tv_nsec = 0;
            timerfd_settime(timer_fd, 0, &timer_spec, NULL);
        } else if (fd == timer_fd) {
            // Handle timer event
            // Close the inactive socket and remove from epoll
            close(socket_fd);
            epoll_ctl(epoll_fd, EPOLL_CTL_DEL, socket_fd, NULL);
        }
    }
}

// Cleanup
close(socket_fd);
close(epoll_fd);
close(timer_fd);

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Retrieve the lastModified value from the File object, which represents the number of milliseconds since January 1, 1970 (Unix timestamp).

#include <iostream>
#include <sys/stat.h>

void setModifiedTime(const std::string& filePath, time_t modifiedTime) {
    struct utimbuf timeBuf;
    timeBuf.actime = modifiedTime; // access time (not modified)
    timeBuf.modtime = modifiedTime; // modified time

    // Set the modified time of the file
    if (utime(filePath.c_str(), &timeBuf) != 0) {
        std::cerr << "Failed to set the modified time of the file." << std::endl;
    }
}

int main() {
    // Example usage
    std::string filePath = "/path/to/file.txt";
    time_t lastModified = selectedFiles[i].lastModified / 1000; // Convert to seconds

    setModifiedTime(filePath, lastModified);

    return 0;
}
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