# Debug using ltrace

By default, the build incorporates ltrace.

## Prerequisite

Set up SSH to establish a secure channel between the host computer and the remote server. For instructions, see [Sign in using SSH](https://docs.qualcomm.com/bundle/publicresource/topics/80-80022-254/how_to.html#use-ssh).

## Debug with ltrace

To debug with ltrace, run the following commands using SSH:

1. Run the process status command:

ps -ef
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    **Sample output:**

339 rpc 0:00 /usr/sbin/rpcbind -w -f

345 root 0:00 /lib/systemd/systemd-journald

373 root 0:00 [kworker/3:6-mm\_]
2. Identify the process ID (PID) of the process that you want to debug.
3. Run the `ltrace` command:

ltrace -p 345
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    In this example, `345` is the PID.

    **Sample output:**

journal\_file\_close(0x25e30170, -1, 0, 0 <unfinished ...>

sockaddr\_un\_unlink(0x25e30170, -1, 0, 0

<unfinished ...>

sd\_journal\_close(0x25e31c00, 1, 3, 0x409e70) = 0

sd\_journal\_close(0x25e31d50, 1, 0, 1) = 0

<... sockaddr\_un\_unlink resumed> ) = 1

<... journal\_file\_close resumed> ) = 1

journal\_file\_close(0x25e30170, -1, 0, 0 <unfinished ...>

sockaddr\_un\_unlink(0x25e30170, -1, 0, 0 <unfinished ...>

sd\_event\_now(15, 0x41ed20, 10, 64) = 10

openat64(2, 0x41ed20, 10, 64 <unfinished ...>

clock\_gettime(2, 0x41ed20, 10, 64) = 6

For more information, see [Linux manual page](https://man7.org/linux/man-pages/man1/ltrace.1.html).

Last Published: May 14, 2026

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