linux 的core file的时间戳怎么样才能变成日期格式

Question

之前问了一个问题：

linux 程序崩溃之后会产生core file，带有时间戳，但是时间戳总是不是很直观，每次都要转换下才能知道是什么时候产生的，怎么样才能让生成的core文件的时间戳变成日期格式，如20160911
这样的
在地址：http://ask.csdn.net/questions/332597

得到了一个朋友的回答：

自己写代码...

先修改 /proc/sys/kernel/core_pattern

|/sbin/genCore %p %t

%p - 获取crash 进程号,也能获取crash进程所在的路径
%t - 时间戳,用于转换成Y/m/d格式

genCore的源代码如下,会在crash进程同一目录下生成core.pid.MYD格式的coredump.

genCore.c
#define _GNU_SOURCE
#include
#include
#include
#include
#include
#include
#include

#define BUF_SIZE 1024
#define FILENAME_MAX_LENGTH 256
#define TIMESTAMP_MAX_LENGTH 20

int
main(int argc, char *argv[])
{
int tot, j;
ssize_t nread;
char buf[BUF_SIZE];
FILE *fp;
char cwd[PATH_MAX];

char fileName[FILENAME_MAX_LENGTH];
char strTimeStamp[TIMESTAMP_MAX_LENGTH];
struct tm *coreTimeStamp;
time_t rawTimeStamp;

/* Change our current working directory to that of the
   crashing process */
snprintf(cwd, PATH_MAX, "/proc/%s/cwd", argv[1]);
chdir(cwd);

/* Write output to file "core.<pid>.<Ymd>" in that directory */
rawTimeStamp = (time_t) (atoi(argv[2]));
coreTimeStamp = localtime(&rawTimeStamp);
strftime(strTimeStamp, TIMESTAMP_MAX_LENGTH,"%Y%m%d",coreTimeStamp);
snprintf(fileName, FILENAME_MAX_LENGTH, "core.%s.%s", argv[1], strTimeStamp);
fp = fopen(fileName, "w+");

if (fp == NULL)
    exit(EXIT_FAILURE);

/* Dump the core dump to file */
while ((nread = read(STDIN_FILENO, buf, BUF_SIZE)) > 0)
    fwrite(buf, nread, 1, fp);

fclose(fp);
exit(EXIT_SUCCESS);

}

功能已经实现，但是core产生的位置我想固定产生到/app/core目录下，在没有使用genCore的时候我知道是这样设置：echo "/app/corefile/core-%e-%p-%t" > /proc/sys/kernel/core_pattern，用了genCore之后就不知道该如何弄了，

应该不能这么搞吧：echo " /app/corefile/|/sbin/genCore %e %p %t " > /proc/sys/kernel/core_pattern

Answer 1

第一步：echo "|/sbin/genCore %e %p %t" > /proc/sys/kernel/core_pattern

第二步：将代码修改为如下：
#define _GNU_SOURCE
#include
#include
#include
#include
#include
#include
#include

#define BUF_SIZE 1024
#define FILENAME_MAX_LENGTH 256
#define TIMESTAMP_MAX_LENGTH 20

int
main(int argc, char *argv[])
{
int tot, j;
ssize_t nread;
char buf[BUF_SIZE];
FILE *fp;
char cwd[PATH_MAX];

char fileName[FILENAME_MAX_LENGTH];
char strTimeStamp[TIMESTAMP_MAX_LENGTH];
struct tm *coreTimeStamp;
time_t rawTimeStamp;

/* Change our current working directory to that of the
   crashing process */
snprintf(cwd, PATH_MAX, "/proc/%s/cwd", argv[1]);
chdir(cwd);

/* Write output to file "core.<pid>.<Ymd>" in that directory */
rawTimeStamp = (time_t) (atoi(argv[2]));
coreTimeStamp = localtime(&rawTimeStamp);
strftime(strTimeStamp, TIMESTAMP_MAX_LENGTH,"%Y%m%d",coreTimeStamp);
snprintf(fileName, FILENAME_MAX_LENGTH, "core.%s.%s.%s", argv[1],argv[2], strTimeStamp);
fp = fopen(fileName, "w+");

if (fp == NULL)
    exit(EXIT_FAILURE);

/* Dump the core dump to file */
while ((nread = read(STDIN_FILENO, buf, BUF_SIZE)) > 0)
    fwrite(buf, nread, 1, fp);

fclose(fp);
exit(EXIT_SUCCESS);

}

第三步：将genCore.c编译为genCore放到/sbin目录下