Output a frame data stream.

Synopsis

lalfr-stream --channel=channel --frame-cache=cachefile [--start-time=tstart] [--duration=deltat]

lalfr-stream --channel=channel --frame-glob=globstring [--start-time=tstart] [--duration=deltat]

Description

The lalfr-stream utility reads a requested interval [tstart,tstart+deltat) of channel data from frame files that are either indexed in the cachefile or matching the pattern globstring as described by glob(3). If tstart is not specified, streaming begins at the beginning of the available data. If deltat is not specified, streaming continues until the end of the available data. The output is written to the standard output in two-column ascii format data in which the first column contains the GPS times of each sample and the second column contains the corresponding sample values.

Options

-h, --help: Prints the help message.
-c channel, --channel=channel: The channel name that is to be read.
-f cachefile, --frame-cache=cachefile: The cachefile indexing the frame files to be used.
-g globstring, --frame-glob=globstring: The globstring identifying the frame files to be used.
-s tstart, --start-time=tstart: The time tstart GPS seconds of the data to read.
-t deltat, --duration=deltat: The duration deltat in seconds of data to read.

Environment

The LAL_DEBUG_LEVEL can used to control the error and warning reporting of lalfr-stream. Common values are: LAL_DEBUG_LEVEL=0 which suppresses error messages, LAL_DEBUG_LEVEL=1 which prints error messages alone, LAL_DEBUG_LEVEL=3 which prints both error messages and warning messages, and LAL_DEBUG_LEVEL=7 which additionally prints informational messages.

Exit Status

The lalfr-stream utility exits 0 on success, and >0 if an error occurs.

Examples

The command:

lalfr-stream -c H1:LSC-STRAIN -g "H-*.gwf" -s 1000000000 -t 1000

will stream 1000 seconds of H1:LSC-STRAIN data beginning at GPS time 1000000000 from frame files matching H-*.gwf in the current directory.

See also: lalfr-vis