# Install classads with Homebrew

Classified Advertisements (used by HTCondor Central Manager). Version 1.0.10 via Homebrew; verified from local package data.

## Install

```sh
sudo av install brew:classads
```

Additional install commands:

### macOS

- Homebrew (100%):

```sh
brew install classads
```

  Evidence: local Homebrew formula metadata

## Package facts

- **Package key:** brew:classads
- **Package manager:** Homebrew
- **Version:** 1.0.10
- **Source summary:** Classified Advertisements (used by HTCondor Central Manager)
- **Homepage:** <https://research.cs.wisc.edu/htcondor/classad/>
- **Generated:** 2026-08-03T19:37:03+00:00

## Executables

- classad_functional_tester (alias)
- classad_functional_tester_ns (alias)
- classad_version (alias)
- classad_version_ns (alias)
- cxi (alias)
- cxi_ns (alias)

## Install behavior

- Bottle: not available

## Freshness

- Page generated: 2026-08-03
- Package-manager version: 1.0.10
## Project history and usage

ClassAds are HTCondor's classified advertisement language and matching mechanism for describing jobs, machines, submitters, resources, and constraints in high-throughput computing systems.

### Project history

The official ClassAds page describes ClassAds as the lingua franca of HTCondor, exchanged by HTCondor processes to describe jobs, workstations, and other resources. The same page states that the ClassAd library is also available as a standalone package outside HTCondor.

HTCondor documentation records a transition from Old ClassAds to New ClassAds: Old ClassAds were tied to HTCondor development libraries, New ClassAds added features and were designed as a standalone library, and HTCondor switched to the New ClassAd library in version 7.5.1.

### Adoption history

The standalone C++ ClassAd distribution has official release history from 0.9.6 in October 2004 through 1.0.10 in April 2011. Homebrew packages that standalone tarball as classads 1.0.10 and reported 101 installs over the prior 365 days.

### How it is used

ClassAds are used for matchmaking: a job ClassAd and a machine ClassAd can refer to one another while expressions evaluate whether constraints are satisfied. The Homebrew package exposes small C++ library utilities such as cxi and classad_version.

### Why package nerds care

ClassAds is package-nerd interesting because Homebrew preserves a standalone slice of HTCondor's scheduler expression language as a small C++ package, separate from the much larger HTCondor system.

### Timeline

- 2004: Official standalone C++ library version 0.9.6 released.
- 2010: HTCondor 7.5.1 switched to the New ClassAd library.
- 2011: Official standalone C++ library version 1.0.10 released.
- 2026: Homebrew formula metadata lists classads 1.0.10 as stable.

### Related projects

- ClassAds are part of the HTCondor software suite and are also documented in the HTCondor manual.
- The official ClassAds page references Java implementations and ClassAd language papers/specifications alongside the C++ library.

### Sources

- <https://htcondor.org/classad/classad.html>
- <https://htcondor.org/classad/c%2B%2Bdoc>
- <https://htcondor.readthedocs.io/en/latest/classads/classad-mechanism.html>
- <https://api.github.com/repos/htcondor/htcondor>
- <https://formulae.brew.sh/api/formula/classads.json>


## Security Notes

narrow executable package without higher-risk signals.

- **Geiger risk:** green / low
- narrow executable package without higher-risk signals


## Combined YAML source

View the package source record on GitHub. [combined/classads.yml](https://github.com/mxcl/pkgdb/blob/main/combined/classads.yml)


## Sources

- pkg.so package database
- Geiger risk classifier
- curated package history
- pkgdb category and tag curation
- cross-ecosystem install command graph