dlv 调试

一、安装

       https://github.com/go-delve/delve

直接去github上查看各种系统的安装教程，应该基本上都是 go get

二、命令

Available Commands:
  attach      Attach to running process and begin debugging.
  connect     Connect to a headless debug server.
  core        Examine a core dump.
  dap         [EXPERIMENTAL] Starts a TCP server communicating via Debug Adaptor Protocol (DAP).
  debug       Compile and begin debugging main package in current directory, or the package specified.
  exec        Execute a precompiled binary, and begin a debug session.
  help        Help about any command
  run         Deprecated command. Use 'debug' instead.
  test        Compile test binary and begin debugging program.
  trace       Compile and begin tracing program.
  version     Prints version.

Flags:
      --accept-multiclient   Allows a headless server to accept multiple client connections.
      --api-version int      Selects API version when headless. New clients should use v2. Can be reset via RPCServer.SetApiVersion. See Documentation/api/json-rpc/README.md. (default 1)
      --backend string       Backend selection (see 'dlv help backend'). (default "default")
      --build-flags string   Build flags, to be passed to the compiler.
      --check-go-version     Checks that the version of Go in use is compatible with Delve. (default true)
      --headless             Run debug server only, in headless mode.
      --init string          Init file, executed by the terminal client.
  -l, --listen string        Debugging server listen address. (default "127.0.0.1:0")
      --log                  Enable debugging server logging.
      --log-dest string      Writes logs to the specified file or file descriptor (see 'dlv help log').
      --log-output string    Comma separated list of components that should produce debug output (see 'dlv help log')
      --only-same-user       Only connections from the same user that started this instance of Delve are allowed to connect. (default true)
      --wd string            Working directory for running the program. (default ".")

Additional help topics:
  dlv backend Help about the --backend flag.
  dlv log     Help about logging flags.

dlv 内部调试命令：

Running the program:
    call ------------------------ Resumes process, injecting a function call (EXPERIMENTAL!!!)
    continue (alias: c) --------- Run until breakpoint or program termination.
    next (alias: n) ------------- Step over to next source line.
    rebuild --------------------- Rebuild the target executable and restarts it. It does not work if the executable was not built by delve.
    restart (alias: r) ---------- Restart process.
    step (alias: s) ------------- Single step through program.
    step-instruction (alias: si)  Single step a single cpu instruction.
    stepout (alias: so) --------- Step out of the current function.

Manipulating breakpoints:
    break (alias: b) ------- Sets a breakpoint.
    breakpoints (alias: bp)  Print out info for active breakpoints.
    clear ------------------ Deletes breakpoint.
    clearall --------------- Deletes multiple breakpoints.
    condition (alias: cond)  Set breakpoint condition.
    on --------------------- Executes a command when a breakpoint is hit.
    trace (alias: t) ------- Set tracepoint.

Viewing program variables and memory:
    args ----------------- Print function arguments.
    display -------------- Print value of an expression every time the program stops.
    examinemem (alias: x)  Examine memory:
    locals --------------- Print local variables.
    print (alias: p) ----- Evaluate an expression.
    regs ----------------- Print contents of CPU registers.
    set ------------------ Changes the value of a variable.
    vars ----------------- Print package variables.
    whatis --------------- Prints type of an expression.

Listing and switching between threads and goroutines:
    goroutine (alias: gr) -- Shows or changes current goroutine
    goroutines (alias: grs)  List program goroutines.
    thread (alias: tr) ----- Switch to the specified thread.
    threads ---------------- Print out info for every traced thread.

Viewing the call stack and selecting frames:
    deferred --------- Executes command in the context of a deferred call.
    down ------------- Move the current frame down.
    frame ------------ Set the current frame, or execute command on a different frame.
    stack (alias: bt)  Print stack trace.
    up --------------- Move the current frame up.

Other commands:
    config --------------------- Changes configuration parameters.
    disassemble (alias: disass)  Disassembler.
    edit (alias: ed) ----------- Open where you are in $DELVE_EDITOR or $EDITOR
    exit (alias: quit | q) ----- Exit the debugger.
    funcs ---------------------- Print list of functions.
    help (alias: h) ------------ Prints the help message.
    libraries ------------------ List loaded dynamic libraries
    list (alias: ls | l) ------- Show source code.
    source --------------------- Executes a file containing a list of delve commands
    sources -------------------- Print list of source files.
    types ---------------------- Print list of types

三、使用

dlv debug

• 如果位于工程目录下，可以dlv debug开始调试；
• 也可以指定目录，dlv debug GoWorks/GoDbg;
• 如果要传入参数，添加–后指定， 如dlv debug GoWorks/GoDbg – -arg1 value

dlv exec

lin@MacBook-Pro test % ls
activitycenter    go.mod        go.sum        main.go        test
lin@MacBook-Pro test % dlv exec ./test 
Type 'help' for list of commands.
(dlv) 

dlv attach

lin@MacBook-Pro / % ps -ef | grep test   
  501 32158  7146   0  8:12下午 ttys000    0:00.00 grep test
  501 32156 31667   0  8:12下午 ttys001    0:00.24 ./test
lin@MacBook-Pro h/ % dlv attach 32156  
Type 'help' for list of commands.
(dlv) -h

注意：在退出时，有可选是否要kill该进程。

dlv core

注意：dlv不支持生成core，可以通过gdb attach上去后，执行gcore来生成core；然后再dlv core来调试。