head

Stop the pipeline after a fixed number of messages.

Synopsis

bgpipe [...] -- head [OPTIONS]

Description

The head stage lets only the first N messages pass and then stops the pipeline. This is useful for sampling or quick tests against a live source.

The message count is taken from messages seen in the stage direction (or both when using -LR). When the limit is reached, the stage passes that message and stops the pipeline.

Options

Option	Type	Default	Description
-n, --count	int	10	Number of messages to pass before stopping

Examples

Stop after 20 updates from a live session:

bgpipe \
    -- connect 192.0.2.1 \
    -- head -n 20 \
    -- stdout

Sample 100 messages in both directions:

bgpipe \
    -- listen :179 \
    -- head -LR -n 100 \
    -- connect 192.0.2.1

See Also

grep, limit, Stages overview