2.3 KiB
procfs
This procfs package provides functions to retrieve system, kernel and process metrics from the pseudo-filesystems /proc and /sys.
WARNING: This package is a work in progress. Its API may still break in backwards-incompatible ways without warnings. Use it at your own risk.
Usage
The procfs library is organized by packages based on whether the gathered data is coming from
/proc, /sys, or both. Each package contains an FS type which represents the path to either /proc, /sys, or both. For example, current cpu statistics are gathered from
/proc/stat and are available via the root procfs package. First, the proc filesystem mount
point is initialized, and then the stat information is read.
fs, err := procfs.NewFS("/proc")
stats, err := fs.Stat()
Some sub-packages such as blockdevice, require access to both the proc and sys filesystems.
fs, err := blockdevice.NewFS("/proc", "/sys")
stats, err := fs.ProcDiskstats()
Building and Testing
The procfs library is normally built as part of another application. However, when making
changes to the library, the make test command can be used to run the API test suite.
Updating Test Fixtures
The procfs library includes a set of test fixtures which include many example files from
the /proc and /sys filesystems. These fixtures are included as a ttar file
which is extracted automatically during testing. To add/update the test fixtures, first
ensure the fixtures directory is up to date by removing the existing directory and then
extracting the ttar file using make fixtures/.unpacked or just make test.
rm -rf fixtures
make test
Next, make the required changes to the extracted files in the fixtures directory. When
the changes are complete, run make update_fixtures to create a new fixtures.ttar file
based on the updated fixtures directory. And finally, verify the changes using
git diff fixtures.ttar.