Gutcheck is a command line program, written in C, whose purpose is to scan a book text file looking for many common proofreading errors. If you run Gutcheck from the command line, its output is a voluminous text file listing many possible errors by line number.

You can run Gutcheck from within Guiguts. Guiguts saves the current document; calls Gutcheck to read the saved file; collects its output; and displays the Gutcheck output in a report window. You inspect the diagnostics in the report window, and click on them to jump to the referenced point in the document window.

To use Gutcheck, first use Fixup>Gutcheck options. This opens a small dialog in which you set the command line options that control what Gutcheck looks for:

The default option set (all un-checked except for the first, "-v") is the recommended set. If the output is overwhelmed with reports on incorrect newlines, set option "-l Do not report non DOS newlines." Setting options "-p" and "-s" to report on unbalanced quotes may or may not produce too much output to be useful. Click OK to accept the options.

After setting the options, use Fixup>Run Gutcheck to initiate a run. The document is saved at this time. Then Gutcheck runs, which takes a few seconds, after which the report window opens:

The first few lines (not shown) are a summary. The line-by-line diagnostics follow. To see an error in context, double-click the line in the report window. The document window scrolls to that line. The insertion point moves to the diagnosed point in the line, if a specific column is mentioned. The document window becomes the active keyboard focus.

Many of the diagnostics are not relevant, at least after you have first inspected them. For example, every use of an accented or Latin-1 character is diagnosed. (And Gutcheck is not designed to process Unicode characters at all; if the document has more than a few characters beyond Latin-1, the output may be unusable.) You can reduce the clutter of the report window in two ways.

When you have dealt with a diagnostic, or have decided that it does not represent a problem, you can right-click that line (Mac: control-click). The line disappears from the report and the document scrolls to the location of the following diagnostic line. You can run quickly through irrelevant diagnostics by right-clicking one after another without moving the mouse.

Sometimes a whole class of diagnostics is not relevant, or not helpful at this stage of editing. For example in the window above, all messages like "Query digit in 016.png" are not helpful just now because page separator lines have not been removed from the file. Diagnostics about long and short lines aren't very relevant until after you have rewrapped the document. You can hide all lines of any class at once. Click the View Options button to open this palette of options:

To hide every one of the "Query digit in..." diagnostics, set the switch half-way down the middle column.

The Hide all and See all buttons set or clear all switches. The Toggle View button inverts all switches: ons become offs and vice-versa. Use the Save My View button to save the present set of switches. The switch settings are "saved" in memory; however, when you next save the document, the switch settings are written into the .bin file and will be available next time you load the document. Use the Load My View button to return to the last-saved setup.