Simple publishing and subscribing via the C interface

[lawaarch]

My pub code

#include <string.h>
#include <stdio.h>
#include "zenoh.h"
 #include"chrono"
 #include <cinttypes>  
int main(int argc, char **argv) 
{
constexpr size_t DATA_SIZE = 4096 * 2160 * 3; // 4K, 3-channel image size

int ITERATIONS = 100;
    z_owned_config_t config;
    z_config_default(&config);
    z_owned_session_t s;
    if (z_open(&s, z_move(config), NULL) < 0) {
        printf("Failed to open Zenoh session\n");
        exit(-1);
    }
    uint8_t * data = (uint8_t *)malloc(DATA_SIZE);
    z_owned_bytes_t payload;
    
    z_view_keyexpr_t key_expr;
    z_view_keyexpr_from_str(&key_expr, "key/expression");

    while(ITERATIONS--)
    { 
        printf("current: %" PRId64 "\n", 
                std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count());
        // z_bytes_from_static_str(&payload, "value");
        z_bytes_from_static_buf(&payload,data,DATA_SIZE);
        z_put(z_loan(s), z_loan(key_expr), z_move(payload), NULL);
    }
    

    z_drop(z_move(s));
    return 0;
}

my sub code

#include <stdio.h>
#include "zenoh.h"
#include "chrono"
#include <cinttypes>
void data_handler(z_loaned_sample_t *sample, void *arg)
{
    printf("current: %" PRId64 "\n",
           std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count());
    // z_view_string_t key_string;
    // z_keyexpr_as_view_string(z_sample_keyexpr(sample), &key_string);
    // z_owned_string_t payload_string;
    // z_bytes_to_string(z_sample_payload(sample), &payload_string);

    // printf(">> Received (%.*s, %.*s)\n",
    //     (int)z_string_len(z_loan(key_string)), z_string_data(z_loan(key_string)),
    //     (int)z_string_len(z_loan(payload_string)), z_string_data(z_loan(payload_string))
    // );
    //  printf(">> Received (%.*s, %.)\n",
    //     (int)z_string_len(z_loan(key_string)), z_string_data(z_loan(key_string))
    // );

    // z_drop(z_move(payload_string));
}

int main(int argc, char **argv)
{
    z_owned_config_t config;
    z_config_default(&config);
    z_owned_session_t s;
    if (z_open(&s, z_move(config), NULL) < 0)
    {
        printf("Failed to open Zenoh session.\n");
        exit(-1);
    }

    z_owned_closure_sample_t callback;
    z_closure(&callback, data_handler, NULL, NULL);

    z_view_keyexpr_t key_expr;
    z_view_keyexpr_from_str(&key_expr, "key/expression");

    z_owned_subscriber_t sub;
    if (z_declare_subscriber(z_loan(s), &sub, z_loan(key_expr), z_move(callback), NULL) < 0)
    {
        printf("Unable to create Zenoh subscriber.\n");
        z_drop(z_move(s));
        exit(-1);
    }

    char c = 0;
    while (c != 'q')
    {
        c = fgetc(stdin);
    }

    z_drop(z_move(sub));
    z_drop(z_move(s));
    return 0;
}

The phenomenon is that sub prints the timestamp every time, and it can be observed that the interval between each timestamp is approximately 30ms.This does not conform to the theoretical standards.
My Zenoh version 1.7.1
My compilation script

#!/bin/bash
set -e

# ===================== 1. 基础路径配置 =====================
ROOT_DIR=$(cd $(dirname $0); pwd)
SDK="/home/lw/lw_work/tools/gcc-arm-10.2-2020.11-x86_64-aarch64-none-linux-gnu"
BUILD_NAME=aarch64_build
INSTALL_DIR="${ROOT_DIR}/${BUILD_NAME}/install"
RUST_TARGET="aarch64-unknown-linux-gnu"


export CARGO_BUILD_TARGET="${RUST_TARGET}"
export TARGET_CC="${SDK}/bin/aarch64-none-linux-gnu-gcc"
export TARGET_AR="${SDK}/bin/aarch64-none-linux-gnu-ar"

# ===================== 2. 检查依赖 =====================
echo "===== 检查依赖 ====="
if ! command -v cargo &> /dev/null; then
    echo "错误：未找到cargo！请先安装Rust工具链"
    exit 1
fi
if [ ! -f "${SDK}/bin/aarch64-none-linux-gnu-gcc" ]; then
    echo "错误：未找到ARM64交叉编译器！"
    exit 1
fi

# ===================== 3. 配置Rust交叉编译 =====================
echo "===== 配置Rust交叉编译 ====="
CARGO_CONFIG_DIR="${HOME}/.cargo"
CARGO_CONFIG_FILE="${CARGO_CONFIG_DIR}/config"
mkdir -p ${CARGO_CONFIG_DIR}
# 关键：无缩进写入配置
cat > ${CARGO_CONFIG_FILE} << EOF
[target.${RUST_TARGET}]
linker = "${SDK}/bin/aarch64-none-linux-gnu-gcc"
ar = "${SDK}/bin/aarch64-none-linux-gnu-ar"
EOF
rustup target add ${RUST_TARGET}

# ===================== 4. 清理旧目录 =====================
echo "===== 清理旧编译目录 ====="
rm -rf ${BUILD_NAME}
mkdir -p ${BUILD_NAME} && cd ${BUILD_NAME}

# ===================== 5. CMake配置（仅保留有效参数） =====================
echo "===== 执行CMake配置 ====="
cmake_cmd=(
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=aarch64
    -DCMAKE_C_COMPILER="${SDK}/bin/aarch64-none-linux-gnu-gcc"
    -DCMAKE_CXX_COMPILER="${SDK}/bin/aarch64-none-linux-gnu-g++"
    -DCMAKE_BUILD_TYPE=Release
    -DCMAKE_INSTALL_PREFIX="${INSTALL_DIR}"
    # 核心：给Cargo传递--target参数
    -DZENOHC_CARGO_FLAGS="--target=${RUST_TARGET};--features=shared-memory"
    -DZENOHC_BUILD_WITH_SHARED_MEMORY=ON
    -DBUILD_SHARED_LIBS=ON
)
cmake "${cmake_cmd[@]}" ..

# ===================== 6. 编译+安装 =====================
echo "===== 编译Zenoh C库 ====="
make -j$(nproc)
echo "===== 安装Zenoh C库 ====="
make install

# ===================== 7. 验证结果 =====================
echo "===== 验证编译结果 ====="
LIB_FILE="${INSTALL_DIR}/lib/libzenohc.so"
if [ -f "${LIB_FILE}" ]; then
    echo "✅ 编译成功！库文件：${LIB_FILE}"
    file ${LIB_FILE}
    if file ${LIB_FILE} | grep -qi "aarch64\|arm64"; then
        echo "✅ 库架构正确（ARM64）"
    else
        echo "❌ 库架构错误！当前是x86_64"
        exit 1
    fi
else
    echo "❌ 编译失败！未找到动态库"
    exit 1
fi

echo "===== 全部完成！安装目录：${INSTALL_DIR} ====="

compiling environment

No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04.6 LTS
Release:        20.04
Codename:       focal