写log日志文件

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <string.h>

int Write_log_file(char *pFilename, char *pBuffer, int data_len)
{
    int ret_val = -1;
    int fd = -1;
    mode_t f_attrib;
    time_t cur_time;
    struct tm *pTm;
    char date_buf[50];

    f_attrib = S_IRWXU | S_IRWXG | S_IRWXO;
    /**/
    fd = open(pFilename, O_RDWR|O_APPEND|O_CREAT, f_attrib);
    if(fd < 0)
    {
        printf("open Failed:%d\n", fd);
        goto _OVER_;
    }

    /**/
    time(&cur_time);
    pTm = localtime(&cur_time);
    snprintf(date_buf, 50, "[%04d-%02d-%02d %02d:%02d:%02d]",
                    pTm->tm_year + 1900,
                    pTm->tm_mon + 1,
                    pTm->tm_mday,
                    pTm->tm_hour,
                    pTm->tm_min,
                    pTm->tm_sec);
    /**/
    ret_val = write(fd, date_buf, strlen(date_buf));
    if(ret_val != (int)strlen(date_buf))
    {
        printf("write Failed:%d\n", ret_val);
        goto _OVER_;
    }

    /**/
    ret_val = write(fd, pBuffer, data_len);
    if(ret_val != data_len)
    {
        printf("write Failed:%d\n", ret_val);
        goto _OVER_;
    }

_OVER_:
    if(fd >= 0)
    {
        close(fd);
    }
    return ret_val;
}

/**/
int main(int argc, char **argv)
{
    int i;
    char buffer[20];

    for(i = 0; i < 20; i++)
    {
        snprintf(buffer, 20, "hello%dhello\n", i);
        Write_log_file((char *)"./a.txt", (char *)buffer, strlen(buffer));
    }

    return 0;
}