---
name: "pmContextUndef"
section: "3"
platform: "linux"
package: "libpcp3-dev"
version: "3.3.3-squeeze3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/pmContextUndef"
---

# pmContextUndef(3)

change current PMAPI context

## NAME

**pmContextUndef** - change current PMAPI context

## C SYNOPSIS

**#include \<pcp/pmapi.h\>**

**void pmContextUndef(void)**

**cc ... -lpcp**

## DESCRIPTION

An application using the Performance Metrics Application Programming Interface (PMAPI) may manipulate several concurrent contexts, each associated with a source of performance metrics, e.g. [**pmcd**(1)](/pmcd/1.md) on some host, or an archive log of performance metrics as created by [**pmlogger**(1)](/pmlogger/1.md).

Calling **pmContextUndef** causes the current PMAPI context to be reset to undefined state which could be use to prevent unintentional communication with PMCD.

## SEE ALSO

[**PMAPI**(3)](/PMAPI/3.md), [**pmDestroyContext**(3)](/pmDestroyContext/3.md), [**pmDupContext**(3)](/pmDupContext/3.md), [**pmNewContext**(3)](/pmNewContext/3.md) and [**pmWhichContext**(3)](/pmWhichContext/3.md).