Introduction

The wgrib2 library can either close or not close the files after calls to the wgrib2 subroutine. Closing the file frees up resources and helps prevent you from getting the "Too Many Files Open" error message. However, reopening files is a slow operation and you usually keep the files open if you plan to read/write to the file again.

If you are reading from a previously opened and not-closed file, you will normally continue reading from where the last call to the wgrib2 subroutine stopped. Sometimes this the preferred behavior. Sometimes, you want the library to start reading the file from the beginning.

The -rewind_proc option rewinds an already open file during the processing phase.

Usage

-rewind_proc FILE
  FILE must be already opened
  This command is only useful in callable wgrib2