---
name: "proc_pid_cmdline"
section: "5"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/proc_pid_cmdline"
---

# proc\_pid\_cmdline(5)

command line

## NAME

/proc/pid/cmdline - command line

## DESCRIPTION

- */proc/*pid*/cmdline*

  This read-only file holds the complete command line for the process, unless the process is a zombie. In the latter case, there is nothing in this file: that is, a read on this file will return 0 characters.

-

  For processes which are still running, the command-line arguments appear in this file in the same layout as they do in process memory: If the process is well-behaved, it is a set of strings separated by null bytes ('\\0'), with a further null byte after the last string.

-

  This is the common case, but processes have the freedom to override the memory region and break assumptions about the contents or format of the */proc/*pid*/cmdline* file.

-

  If, after an [**execve**(2)](/execve/2.md), the process modifies its *argv* strings, those changes will show up here. This is not the same thing as modifying the *argv* array.

-

  Furthermore, a process may change the memory location that this file refers via [**prctl**(2)](/prctl/2.md) operations such as **PR\_SET\_MM\_ARG\_START**.

-

  Think of this file as the command line that the process wants you to see.

## SEE ALSO

[**proc**(5)](/proc/5.md)