@PipelineProperty(description = "Choose the name of the file to write.",
            displayPriority = 2)
    public void setFileName(final String fileNamePattern) {
        this.fileNamePattern = fileNamePattern;
    }
Parses a POSIX-style file permission string like "rwxr--r--"
stroom-pipeline/src/main/java/stroom/pipeline/writer/RollingFileAppender.java