---
name: "atf-check"
section: "1"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/atf-check"
---

# atf-check(1)

executes a command and analyzes its results

## NAME

**atf-check** – executes a command and analyzes its results

## SYNOPSIS

**atf-check** \[**-s** *qual:value*\] \[**-o** *action:arg* *...*\] \[**-e** *action:arg* *...*\] \[**-x**\] \[**-r** *timeout\[:interval\]*\] *command*

## DESCRIPTION

**atf-check** executes a given command and analyzes its results, including exit code, stdout, and stderr.

Test cases must use [atf-sh(3)](/atf-sh/3.md)'s **atf\_check** builtin function instead of calling this utility directly.

**atf-check** will execute the provided command and apply checks specified by arguments. By default **atf-check** acts as if it was run with **-s** *exit:0* **-o** *empty* **-e** *empty*.

**-o** *empty* and **-e** *empty* may be specified multiple times. If they are specified multiple times, the checks will be applied to the appropriate stream in the order they were provided.

The following options are available:

- **-s** *qual:value*

  Analyzes termination status. Must be one of:

  - *exit:\<value\>*

    checks that the program exited cleanly and that its exit status is equal to *value*. The exit code can be omitted altogether, in which case any clean exit is accepted.

  - *ignore*

    ignores the exit check.

  - *signal:\<value\>*

    checks that the program exited due to a signal, and (optionally) checks that the signal which terminated the process is *value*. The signal can be specified as a number, a name, or it can be omitted altogether (in which case any signal is accepted).

    Most of these checkers can be prefixed by the ‘not-’ string, which effectively reverses the check.

- **-o** *action:arg*

  Analyzes standard output. Must be one of:

  - *empty*

    checks that stdout is empty

  - *ignore*

    ignores stdout

  - *file:\<path\>*

    compares stdout with given file

  - *inline:\<value\>*

    compares stdout with inline value

  - *match:\<regexp\>*

    looks for a regular expression in stdout

  - *save:\<path\>*

    saves stdout to given file

    Most of these checkers can be prefixed by the ‘not-’ string, which effectively reverses the check.

- **-e** *action:arg*

  Analyzes standard error. The usage is identical to **-o**.

- **-x**

  Executes *command* as a shell command line, executing it with the system shell defined by *ATF\_SHELL*. You should avoid using this flag if at all possible to prevent shell quoting issues.

- **-r** *timeout\[:interval\]*

  Repeats failed checks until the *timeout* (in seconds) expires. If unspecified, the default *interval* (in milliseconds) is 50 ms. This can be used to wait for an expected update to the contents of a file.

## ENVIRONMENT

- *ATF\_SHELL*

  Path to the system shell to be used when the **-x** is given to run commands.

## EXIT STATUS

**atf-check** exits 0 on success, and other (unspecified) value on failure.

## EXAMPLES

The following are sample invocations from within a test case. Note that we use the **atf\_check** function provided by [atf-sh(3)](/atf-sh/3.md) instead of executing **atf-check** directly:

```
# Exit code 0, nothing on stdout/stderr
atf_check true
# Typical usage if failure is expected
atf_check -s not-exit:0 false
# Checking stdout/stderr
echo foobar >expout
atf_check -o file:expout -e inline:"xx\tyy\n" \
    -x 'echo foobar ; printf "xx\tyy\n" >&2'
# Checking for a crash
atf_check -s signal:sigsegv my_program
# Combined checks
atf_check -o match:foo -o not-match:bar echo foo baz
# Wait 5 seconds for a line to show up in a file
( sleep 2 ; echo "testing 123" > $test_path ) &
atf-check -o ignore -e ignore -s exit:0 -r 5 \
    grep "testing 123" $test_path
```

## SEE ALSO

[atf-sh(1)](/atf-sh/1.md)