GDBSERVER(1)

📦 version 2026.0.1.27+c9c3d3e3_ddb4_490e_bb41_6e9041ba32a7, in arch rolling

🎀 GDBSERVER 🎀

💫 NAME 💫

gdbserver — the Remote Server for the GNU Debugger, aka the little icon that lets you debug on a whole different machine, no cap. (This is the gdbserver(1) page from the GNU Development Tools set, bestie — buckle up 💖)

✨ SYNOPSIS ✨

gdbserver comm prog [args...]

gdbserver --attach comm pid

gdbserver --multi comm

🦋 DESCRIPTION 🦋

Okay so gdbserver is literally the program that lets you run GDB on a different machine than the one that's actually running the program you're debugging. Two machines, one debug session, main character energy 🫶

🌸 Usage (server (target) side) 🌸

First things first: you gotta get a copy of the program you wanna debug onto the target system. It can be stripped to save space if needed — gdbserver genuinely does not care about symbols, like at all. All the symbol handling is taken care of by the GDB running on the host system. Not its job, not its problem 💅

So to use the server, you log on to the target system and run the gdbserver program. You must tell it three things: (a) how to communicate with GDB, (b) the name of your program, and (c) its arguments. The general syntax is:

target> gdbserver <comm> <program> [<args> ...]

For example, using a serial port, you might say:

target> gdbserver /dev/com1 emacs foo.txt

This tells gdbserver to debug emacs with an argument of foo.txt, and to communicate with GDB via /dev/com1. Then gdbserver just waits patiently for the host GDB to hit it up. So patient. So demure.

To use a TCP connection instead, you could say:

target> gdbserver host:2345 emacs foo.txt

Pretty much the same thing as the last example, except now we're communicating with the "host" GDB via TCP 🔥 The host:2345 argument means we're expecting to see a TCP connection from "host" to local TCP port 2345. (Currently, the "host" part is ignored — it's giving decorative, honestly.) You can choose any number you want for the port number as long as it does not conflict with any existing TCP ports on the target system. That same port number must be used in the host GDB's target remote command, which we'll get to in a sec. And heads up: if you chose a port number that conflicts with another service, gdbserver will print an error message and exit. Dramatic but fair 💀

gdbserver can also attach to running programs. That's what the --attach argument is for. The syntax is:

target> gdbserver --attach <comm> <pid>

pid is the process ID of a currently running process. And ngl, you don't even need to point gdbserver at a binary for the running process. Slay.

To start gdbserver without supplying an initial command to run or a process ID to attach, use the --multi command line option. In that case you should connect using target extended-remote to start the program you want to debug:

target> gdbserver --multi <comm>

🧚 Usage (host side) 🧚

You need an unstripped copy of the target program on your host system, because GDB needs to examine its symbol tables and such. (Yes, this is the opposite of the target side. Balance ✨)

Start up GDB as you normally would, with the target program as the first argument. (You may need to use the --baud option if the serial line is running at anything except 9600 baud.) That is gdb TARGET-PROG, or gdb --baud BAUD TARGET-PROG.

After that, the only new command you need to know about is target remote (or target extended-remote). Its argument is either a device name (usually a serial device, like /dev/ttyb), or a HOST:PORT descriptor. For example:

(gdb) target remote /dev/ttyb

communicates with the server via serial line /dev/ttyb, and:

(gdb) target remote the-target:2345

communicates via a TCP connection to port 2345 on host the-target, where you previously started up gdbserver with the same port number. 👑

⚠️ Note that for TCP connections, you must start up gdbserver prior to using the target remote command, otherwise you may get an error that looks something like Connection refused. Order matters, bestie 😭

gdbserver can also debug multiple inferiors at once — it's described in the GDB manual in node "Inferiors Connections and Programs", and the shell command is literally:

info -f gdb -n 'Inferiors Connections and Programs'

In that case use the extended-remote GDB command variant:

(gdb) target extended-remote the-target:2345

The gdbserver option --multi may or may not be used in that case. Your call, no pressure 🦋

💖 OPTIONS 💖

There are three different modes for invoking gdbserver:

  • Debug a specific program specified by its program name:
gdbserver <comm> <prog> [<args>...]

The comm parameter specifies how the server should communicate with GDB; it is either a device name (to use a serial line), a TCP port number (":1234"), or "-" or "stdio" to use stdin/stdout of gdbserver. Specify the name of the program to debug in prog. Any remaining arguments will be passed to the program verbatim. When the program exits, GDB will close the connection, and gdbserver will exit. Clean exit, cute exit 🎀

  • Debug a specific program by specifying the process ID of a running program:
gdbserver --attach <comm> <pid>

The comm parameter is as described above. Supply the process ID of a running program in pid; GDB will do everything else. Like with the previous mode, when the process pid exits, GDB will close the connection, and gdbserver will exit.

  • Multi-process mode — debug more than one program/process:
gdbserver --multi <comm>

In this mode, GDB can instruct gdbserver which command(s) to run. Unlike the other 2 modes, GDB will not close the connection when a process being debugged exits, so you can debug several processes in the same session. Obsessed 💜

In each of the modes you may specify these options:

  • --help — lists all the options, with brief explanations. The literal "help me help you" of flags 🫶
  • --version — this option causes gdbserver to print its version number and exit.
  • --attach — gdbserver will attach to a running program. The syntax is:
target> gdbserver --attach <comm> <pid>

pid is the process ID of a currently running process. It isn't necessary to point gdbserver at a binary for the running process.

  • --multi — to start gdbserver without supplying an initial command to run or process ID to attach, use this command line option. Then you can connect using target extended-remote and start the program you want to debug. The syntax is:
target> gdbserver --multi <comm>
  • --debug[=option1,option2,...] — instructs gdbserver to display extra status information about the debugging process. This option is intended for gdbserver development and for bug reports to the developers. (It's the devs' little peek behind the curtain 👀)

Each option is the name of a component for which debugging should be enabled. The list of possible options is all, threads, event-loop, remote. The special option all enables all components. The option list is processed left to right, and an option can be prefixed with the - character to disable output for that component, so you could write:

target> gdbserver --debug=all,-event-loop

to turn on debug output for all components except event-loop. If no options are passed to --debug then this is treated as equivalent to --debug=threads. And FYI — this could change in future releases of gdbserver, so don't get too attached 💅

  • --debug-file=filename — instructs gdbserver to send any debug output to the given filename. This option is intended for gdbserver development and for bug reports to the developers.
  • --debug-format=option1[,option2,...] — instructs gdbserver to include extra information in each line of debugging output.
  • --wrapper — specify a wrapper to launch programs for debugging. The option should be followed by the name of the wrapper, then any command-line arguments to pass to the wrapper, then -- indicating the end of the wrapper arguments. Little wrapper sandwich, iykyk 🥪
  • --once — by default, gdbserver keeps the listening TCP port open, so that additional connections are possible. However, if you start gdbserver with the --once option, it will stop listening for any further connection attempts after connecting to the first GDB session. One and done, periodt 🔥

🌈 ENVIRONMENT 🌈

Okay so this section is literally empty in the original page — no environment variables listed, nothing to see here, moving right along 🦋

⭐ SEE ALSO ⭐

The full documentation for GDB is maintained as a Texinfo manual. If the info and gdb programs and GDB's Texinfo documentation are properly installed at your site, the command

info gdb

should give you access to the complete manual. Go off, info 👑

Also on the reading list: Using GDB: A Guide to the GNU Source-Level Debugger, Richard M. Stallman and Roland H. Pesch, July 1991. Vintage. Iconic. 🌸

Copyright (c) 1988-2026 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with the Invariant Sections being "Free Software" and "Free Software Needs Free Documentation", with the Front-Cover Texts being "A GNU Manual," and with the Back-Cover Texts as in (a) below.

(a) The FSF's Back-Cover Text is: "You are free to copy and modify this GNU Manual. Buying copies from GNU Press supports the FSF in developing GNU and promoting software freedom." @sp 1 Copyright (c) 2026, Intel Corporation. Intel's modifications are provided pursuant to the GNU Free Documentation license.

💌 k that's the whole page bestie!! this one came from source/version gdb-17.1.2026.be1840694+ and it's dated 2026-04-07 — go debug something iconic, mwah 🎀💖✨
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