golang coredump

golang生成coredump文件
refer:
    https://blog.csdn.net/xmcy001122/article/details/105665732
    http://t.zoukankan.com/lit10050528-p-4811833.html

1.设置coredump文件
1).临时设置
    echo "/tmp/core-%e-%p-%s-%t" > /proc/sys/kernel/core_pattern
    echo 1 > /proc/sys/kernel/core_pid
2).永久设置
    echo -e "\nkernel.core_pattern=/tmp/core-%e-%p-%s-%t" >> /etc/sysctl.conf
    echo -e "\nkernel.core_uses_pid = 1" >> /etc/sysctl.conf
    sysctl -p /etc/sysctl.conf


2.设置环境变量
echo "GOTRACEBACK=crash" >> ~/.bashrc

3.执行程序
go build -o meng.out meng.go
./meng.out
或者2，3步骤合并：
    GOTRACEBACK=crash ./meng.out
    
4.调试coredump
gdb ./meng.out /tmp/core-meng-399155-6-1669296379    
或
dlv ./meng.out /tmp/core-meng-399155-6-1669296379    
>>
>>bt
 0  0x000000000045cf41 in runtime.raise
    at /usr/local/src/go/src/runtime/sys_linux_amd64.s:165
 1  0x0000000000443a25 in runtime.dieFromSignal
    at /usr/local/src/go/src/runtime/signal_unix.go:769
 。。。。。。
10  0x000000000048ae1f in main.doCommitTask.func1
    at ./meng.go:27
>>frame 10(报错所在栈)
>>list

5.附：meng.go

 1 package main
 2 
 3 import (
 4     "errors"
 5     "fmt"
 6 
 7     "time"
 8     "runtime"
 9     "path"
10 )
11 
12 func main() {
13     fmt.Printf("Hello world!\n")    
14     taskIds := make([]int32, 0)
15     go doCommitTask(&taskIds)
16     time.Sleep(10*time.Second)
17     fmt.Printf("taskIds=%v\n", taskIds)
18 }
19 
20 func doCommitTask(taskIds *[]int32) {
21     defer func() {
22         err := recover()
23         if err != nil {
24             fmt.Printf("error: err=%v\n", err)
25         }
26         fmt.Printf("defer: now=%v\n", time.Now())
27         panic("now")
28     }()
29     fmt.Printf("doCommitTask: start2\n")
30     panic("jack at home2")
31     for i := int32(0); i < 100; i += 1 {
32         *taskIds = append(*taskIds, i)
33     }
34 }
35 
36 
37 func play() {
38     defer func() {
39         if err := recover(); err != nil {
40             fmt.Errorf("panic in safeGo: %v", err)
41         }
42     }()
43     fmt.Printf("player: hello\n")
44     err := errors.New("player stop")
45     panic(err)
46     fmt.Printf("player: world\n\n")
47 }
48 
49 func SafeGo(fun func()) {
50     defer func() {
51         if err := recover(); err != nil {
52             fmt.Errorf("panic in safeGo: %v", err)
53         }
54     }()
55     fun()
56 }
57 
58 func getRootPath(skip int) string {
59     pc, fileName, line, ok := runtime.Caller(skip)
60     if !ok {
61         fmt.Printf("StartUp: runtime.Caller is error.\n")
62         return ""
63     }
64     funcName := runtime.FuncForPC(pc).Name()
65     rootPath := path.Dir(fileName)
66     fmt.Printf("getRootPath: skip=%d, funcName=%s, rootPath=%s, fileName=%s, line=%d.\n", skip, funcName, rootPath, fileName, line)
67     GetNextZeroTime()
68     return rootPath
69 }
70 
71 //当地时间下一次0点
72 func GetNextZeroTime() int64 {
73     nowTime := time.Now()
74     now := nowTime.Unix()
75     _, offsetSeconds := nowTime.Zone()          //相对于utc时区偏移秒数
76     sec := (now + int64(offsetSeconds)) % 86400 //相对于当前时区0点偏移秒数
77     return now - sec + 86400
78 }
79 
80 func PrintLatestStack(playerId int32, skip int) {
81     fmt.Printf("PrintLatestStack: playerId=%d, traces:\n", playerId)
82     pcs := make([]uintptr, 10)
83     n := runtime.Callers(skip+2, pcs)
84     for i := 0; i < n; i += 1 {
85         pc := pcs[i]
86         runFunc := runtime.FuncForPC(pc)
87         fileName, line := runFunc.FileLine(pc)
88         fmt.Printf("funcName=%s, fileName=%s, line=%d.\n", runFunc.Name(), fileName, line)
89     }
90 }