Input Pipes
In the setup utility, the IRIS input process uses either the Pathnames or the Pipe command line format to launch an input pipe. Vaisala recommends the Pathnames format, which invokes the pipe program with the following command line:
$ <pipe-path> --ip=<in-path> --op=<out-path> --device=<number>The information passed back to the calling program is the 8-bit exit status.
Note that:
- Pipes must explicitly open the input and output files.
- The pipe program must write diagnostic information to a log file. Vaisala recommends writing to the ${IRIS_LOG} directory.
| Message | Description |
|---|---|
| EXIT_SUCCESS (0) | Message returned in normal cases. |
| EXIT_FAILURE (1) | IRIS sends the messages: Error running pipe, check log. |
| EXIT_RERUN (2) |
The pipe has produced a normal output, and needs to produce a second output file but is unable to do so. The pipe must store information about the second output on disk. Vaisala recommends writing this in the ${IRIS_TEMP} directory. IRIS processes the first output, then reinvokes the pipe with the following command line: When the pipe is called, it can retrieve the stored information and write the second output to the specified pathname. |
| EXIT_NOTHING (3) |
The pipe ran without error, but no output was produced. Useful for a pipe that must read several input files before producing an output file. IRIS ignores and deletes the output file. For example, the
|