---
name: "stapvars"
section: "3stap"
platform: "linux"
package: "systemtap"
version: "5.6-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/stapvars"
---

# stapvars(3stap)

systemtap variables

## NAME

stapvars - systemtap variables

## DESCRIPTION

The following sections enumerate the public variables provided by standard tapsets installed, (the installation path is show in the stappaths (7) manual page).  Each variable is described with a type, and its behavior/restrictions. The syntax is the same as printed with the  *stap* option *-p2*. Examples:

- example1:long

  Variable "example1" contains an integer.

- example2:string \[long\]

  Variable "example2" is an array of strings, indexed by integers.

### ARGV

- argc:long

  Contains the value of the $# value: the number of command line arguments passed to the systemtap script. It is initialized with an implicit begin(-1) probe.

- argv:string \[long\]

  Contains each command line argument as a string.  argv\[1\] will equal @1 if there was at least one command line argument.  Arguments beyond #32 are not transcribed, and produce a warning message within the begin(-1) probe that initializes this array.

### NULL

- NULL:long

  Simply defined as the number 0.

## FILES

- More files and their corresponding paths can be found in the stappaths (7) manual page.

  ## SEE ALSO

```
stap(1)
stappaths(7)
```