嵌入式c语言，在这段c代码里加入一个sed i，使得开发板下的/dev/ttyUSB1被换成/dev/ttyUSB3（相关搜索：嵌入式|c语言）

#include <stdlib.h>
#include <stdio.h>

int main() {
    // 原始代码
    char code[] = "if (ret == get_keywork_from_file(\"/sys/kernel/debug/usb/devices\", \"6002\", line, sizeof(line))){\n \tsleep(1);\n \tmyPipe(\"echo -e \\\"AT+QCCID\\r\\\" | microcom -t 3 /dev/ttyUSB1 2>&1\", &cimi);\n \tsleep(1);\n \tmyPipe(\"echo -e \\\"AT+CSQ\\r\\\" | microcom -t 3 /dev/ttyUSB1 2>&1\", &buff);\n}";

    // 替换字符串
    char* modified_code = strstr(code, "/dev/ttyUSB1");
    if (modified_code != NULL) {
        // 创建新的字符串
        char* new_code = malloc(strlen(code) + strlen(modified_code) + 10);
        strncpy(new_code, code, modified_code - code);
        new_code[modified_code - code] = '\0';
        strcat(new_code, "/dev/ttyUSB3");
        strcat(new_code, modified_code + strlen("/dev/ttyUSB1"));

        // 使用sed命令替换
        char command[100];
        sprintf(command, "echo \"%s\" | sed 's/\\/dev\\/ttyUSB1/\\/dev\\/ttyUSB3/g'", new_code);
        system(command);

        free(new_code);
    }

    return 0;
}