MGDIFF(1x)

📦
version 1.0 · 2 versions
  • 1.0 · debian bookworm, debian trixie, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking (latest)
  • 1.0 · ubuntu jammy
, in debian bookworm, debian trixie, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

🦋 MGDIFF(1x) 🦋

💫 NAME 💫

mgdiff — a Motif-based graphical file difference browser ✨ (it's literally diff, but make it a whole aesthetic)

🌸 SYNOPSIS 🌸

mgdiff [-toolkitoption ...] [-quit] [-file name] [-args diffargs] [file1 file2]

💖 DESCRIPTION 💖

Okay bestie, listen. Mgdiff is a graphical front end to the diff command. It lets you look at the differences between two ASCII files in context — like, side by side, with your own two eyes — and, if you want, it'll write out a third file that's your own hand-picked merge of the two. 🫶

The inspo was a similar program called gdiff, which only runs on Silicon Graphics workstations and for which source code is not provided. (So like... we can't even peek. Tragic. 😭)

The program takes as arguments various flags (they're all down in the next section, don't worry) plus the names of two files to compare. Either filename — but not both — may be given as - to use standard input instead. 💅

The resulting display is mostly two panes of text. The one on the left is the first file you specified, and the one on the right is the second file you specified. Between and below the text panes are scrollbars that let you change the visible portions of the two files being compared. On top of that, the program implements the Scrolled Region recommendations of Section 2.3.4 of the OSF/Motif Style Guide (release 1.1), meaning the arrow and paging keys will work to scroll as well. 👑

Above each text pane sits the name of the file in that pane and the line number in the file that's currently being displayed.

The text in each of the text panes is divided into blocks of lines that are color-coded with one of five different colors. That color tells you the block:

  • differs between the two files
  • is identical between the two files
  • has been inserted in one file or the other
  • is for display purposes (to match an inserted block in the other file)
  • has been selected by the user (for writing to a merged file)

These colors can be modified by the user via X resources — go check the RESOURCES section of this manual page. ✨ A legend display of the colors and their meanings is available using the Help menu.

On the right-hand side of the display is an overview area; this shows the files in their entirety. The sliders in the overview area track the lines being displayed in the text panes. So useful, honestly.

At the top of the display is a Motif menu bar; those functions get their own whole section below (the MENUS section). 🎀

⏳ History tea, no cap: Earlier versions of this program (pre 2003) only allowed the selection of the left hand side difference or the right hand side difference. It also would not allow a file to be saved with unselected blocks. The current version allows the user to select both sides of a difference by selecting blocks using the middle mouse button. When both sides of a difference are selected, both blocks will be saved to the merged file and marked in a similar manner to the way CVS marks merges that require manual resolution of conflicting changes. In addition, the current version also allows saving of a merged file with unselected blocks. In this case, the merged file will contain neither the left hand side nor the right hand side of the unselected blocks. 💀 (fr fr, read that twice)

🎀 COMMAND LINE OPTIONS 🎀

  • -toolkitoption — These are the standard options accepted by all applications that use the X Toolkit Intrinsics. See the OPTIONS section in the X(1) manual page. 📖
  • -quit — This option sets the resource Mgdiff.quitIfSame to "true". This will cause the program to exit immediately without bringing up a window if the two files have no differences (as determined by the diff command). Lowkey the chillest flag. 😌
  • -args diffargs — This option sets the resource Mgdiff.diffArgs to the value of the diffargs argument. These flags are passed to the diff command that actually computes the differences between the two files. Since any argument can be passed, it is possible to specify flags that cause the diff command to fail, or to generate output in a different format that will cause mgdiff to fail. 😭 So like, be careful, bestie.

For most versions of diff, only three flags make any sense:

  • -b — causes diff to ignore trailing blanks (spaces and tabs) and to treat all other strings of blanks as equivalent.
  • -w — ignores blanks and treats strings of blanks as equivalent.
  • -i — ignores case when comparing letters.
  • -file name — This command sets the resource Mgdiff.filename to the value of the name argument. mgdiff uses this string to display over a file read from standard input. 🦋

The menubar contains the following menu topics as CascadeButtons: File, View, Select, Options and Help. The rest of this section discusses each menu entry, showing its name and accelerator, if any. ✨

📁 File 📁

This pulldown menu controls file access:

  • Open... — Ctrl+O — Brings up the "Open Files" FileSelectionDialog to allow the user to open two files for comparison. 🫶
  • Open Left... — Ctrl+L — Brings up the "Open File" FileSelectionDialog to allow the user to specify a file to open and compare with the already opened right-hand file.
  • Open Right... — Ctrl+R — Brings up the "Open File" FileSelectionDialog to allow the user to specify a file to open and compare with the already opened left-hand file.
  • Reload Both — Meta+R — Re-runs diff on both the currently opened files. 🔄
  • Save As... — Ctrl+S — Brings up the "Save File" FileSelectionDialog to allow the user to specify an output file for writing the merged file; this is an application modal dialog. The program will allow the user to overwrite an existing file but pops up a QuestionDialog to allow the user to cancel the operation if desired. If there are any unselected areas of difference between the two files, the user is asked whether they want to continue or cancel the operation. If the user continues, the output file will contain none of the unselected blocks. ⚠️
  • Save As Left... — Saves the merged file to the location given by the left hand side file location. The user will be asked if they are sure they wish the existing file to be overwritten. As with the "Save As", if there are any unselected areas of difference between the two files the user asked whether they want to continue or cancel the operation. If the user continues, the output file will contain none of the data in the unselected blocks.
  • Save As Right... — Saves the merged file to the location given by the right hand side file location. The user will be asked if they are sure they wish the existing file to be overwritten. As with the "Save As", if there are any unselected areas of difference between the two files the user asked whether they want to continue or cancel the operation. If the user continues, the output file will contain none of the data in the unselected blocks.
  • Exit — Ctrl+C — Exits the program immediately. 💀 bye bestie

👀 View 👀

This pulldown menu contains commands for moving through the files.

  • Previous — Ctrl+P — Scrolls both file views so that the previous area of difference is Mgdiff.linesOfContext lines from the top of the application window.
  • Next — Ctrl+N — Scrolls both file views so that the next area of difference is Mgdiff.linesOfContext lines from the top of the application window.
  • Next Unselected — Ctrl+U — Scrolls both file views so that the next unselected area of difference is Mgdiff.linesOfContext lines from the top of the application window.

✅ Select ✅

The two files being compared can optionally be merged into one file. To do this, the user must select, for each area of difference between the two files, which version should be written to the merged file. The menu entries in this pulldown menu allow the user to select or unselect differences in groups rather than individually. So efficient, we love her. 💅

  • Left All — For all areas of difference between the two files, select the left-hand file version.
  • Right All — For all areas of difference between the two files, select the right-hand file version.
  • Unselect All — Unselects all areas of difference in both files.

⚙️ Options ⚙️

This pulldown menu controls miscellaneous appearance and/or behavior options.

  • Overview — Ctrl+W — This menu entry toggles the presence of the overview area on the right-hand side of the application window. The default value for this toggle is controlled by a resource, Mgdiff.overview, which is described in the RESOURCES section. ✨
  • Horizontal Scrollbar — Ctrl+H — This menu entry toggles the presence of the horizontal scrollbar at the bottom of the application window. The default value for this toggle is controlled by a resource, Mgdiff.horzScrollbar, which is described in the RESOURCES section.
  • Drag Scroll — Ctrl+D — This menu entry toggles the behaviour of the scrollbars in the application window. When set, dragging the slider of a scrollbar results in an immediate change in the view of the text being compared. When unset, the view is only changed at the end of a slider drag (when the mouse button is released.) This setting might be preferred on a slower X server. 🐢 The default value for this toggle is controlled by a resource, Mgdiff.dragScroll, which is described in the RESOURCES section.

🆘 Help 🆘

This pulldown menu displays commands for obtaining help on or information about mgdiff.

  • Version... — Ctrl+V — Brings up an InformationDialog with author and version information.
  • Manual Page... — Ctrl+M — Brings up a DialogShell with a ScrolledText widget containing this manual page. The command for generating this is customizable via a resource, Mgdiff.manCommand, which is described in the RESOURCES section. 📖
  • Color Legend... — Ctrl+G — Brings up a DialogShell which summarizes the use of color in encoding the types of differences between the two files being compared. 🌈

✨ OTHER DISPLAYS/CONTROLS ✨

ok so you can literally teleport to a specific spot in the two files by using BDrag in the overview area 💅

The program uses what the OSF/Motif Style Guide calls "multiple selection" to pick individual blocks for writing to a merged file. Here's the tea 🍓:

  • Clicking BSelect on an unselected block adds it to the list of selected blocks ✨
  • Clicking BSelect on a selected block removes it from the list of selected blocks 🙈
  • Also, clicking BSelect on an unselected block which is opposite a selected block (in the other text panes) removes the selected block from the list of selected blocks 👑

And the numbers in those lil small boxes next to the file names? Those are the line numbers of the lines at the top of the text panes. lowkey useful 🎀

🌈 WIDGETS 🌈

What follows is the hierarchy of Motif widgets, as generated by editres(1). The hierarchical structure of the widget tree is reflected in the indentation, so like, the vibes of the spacing ARE the structure 💖 Each line consists of the widget class name followed by the widget instance name. This information might be useful if you wish to customize the appearance of the program via resource settings. iykyk 🧚

Mgdiff  mgdiff
     XmMainWindow  mainw
          XmSeparatorGadget  MainWinSep1
          XmSeparatorGadget  MainWinSep2
          XmSeparatorGadget  MainWinSep3
          XmRowColumn  menubar
               XmCascadeButtonGadget  button_0
               XmCascadeButtonGadget  button_1
               XmCascadeButtonGadget  button_2
               XmCascadeButtonGadget  button_3
               XmCascadeButtonGadget  button_4
               XmMenuShell  popup_file_menu
                    XmRowColumn  select_menu
                         XmPushButtonGadget  button_0
                         XmPushButtonGadget  button_1
                         XmSeparatorGadget  separator_0
                         XmPushButtonGadget  button_2
                    XmRowColumn  file_menu
                         XmPushButtonGadget  button_0
                         XmPushButtonGadget  button_1
                         XmPushButtonGadget  button_2
                         XmPushButtonGadget  button_3
                         XmPushButtonGadget  button_4
                         XmSeparatorGadget  separator_0
                         XmPushButtonGadget  button_5
                         XmPushButtonGadget  button_6
                         XmSeparatorGadget  separator_1
                         XmPushButtonGadget  button_7
                    XmRowColumn  options_menu
                         XmToggleButtonGadget  button_0
                         XmToggleButtonGadget  button_1
                         XmToggleButtonGadget  button_2
                    XmRowColumn  help_menu
                         XmPushButtonGadget  button_0
                         XmPushButtonGadget  button_1
                         XmPushButtonGadget  button_2
                    XmRowColumn  view_menu
                         XmPushButtonGadget  button_0
                         XmPushButtonGadget  button_1
                         XmPushButtonGadget  button_2
          XmForm  form1
               XmFrame  frame1
                    XmForm  form3
                         XmScrollBar  sbl
                         XmDrawingArea  dam
                         XmScrollBar  sbr
               XmFrame  frame2
                    XmForm  form4
                         XmForm  form2
                              XmScrollBar  sb
                              XmForm  form21
                                   XmFrame  frame3
                                        XmLabel  fnamel
                                   XmFrame  frame31
                                        XmTextField  linenuml
                              XmForm  form22
                                   XmFrame  frame4
                                        XmLabel  fnamer
                                   XmFrame  frame41
                                        XmTextField  linenumr
                              XmDrawingArea  textl
                              XmDrawingArea  textr
                         XmScrollBar  sbh
     XmDialogShell  version_popup
          XmMessageBox  version
               XmLabelGadget  symbol
               XmLabelGadget
               XmSeparatorGadget  separator
               XmPushButtonGadget  OK
               XmPushButtonGadget  Cancel
               XmPushButtonGadget  Help
     XmDialogShell  manualpage_popup
          XmForm  manualpage
               XmPanedWindow  pane
                    XmScrolledWindow  help_textSW
                         XmScrollBar  vbar
                         XmText  help_text
                    XmForm  form2a
                         XmPushButton  OK
                    XmSash  sash
                    XmSeparatorGadget  separator
                    XmSash  sash
                    XmSeparatorGadget  separator
     XmDialogShell  legend_popup
          XmForm  legend
               XmPanedWindow  pane
                    XmRowColumn  rc
                         XmLabel  label1
                         XmLabel  label2
                         XmLabel  label3
                         XmLabel  label4
                         XmLabel  label5
                    XmForm  form2a
                         XmPushButton  OK
                    XmSash  sash
                    XmSeparatorGadget  separator
                    XmSash  sash
                    XmSeparatorGadget  separator
     XmDialogShell  werror_popup
          XmMessageBox  werror
               XmLabelGadget  symbol
               XmLabelGadget
               XmSeparatorGadget  separator
               XmPushButtonGadget  OK
               XmPushButtonGadget  Cancel
               XmPushButtonGadget  Help

💜 X RESOURCES 💜

bestie, this is where you get to customize the whole LOOK of the thing. slay 💅

  • Mgdiff.diffForeground: black
  • Mgdiff.diffBackground: yellow

These colors are for blocks which differ between files. 🍋

  • Mgdiff.sameForeground: black
  • Mgdiff.sameBackground: grey

These colors are for blocks which are identical between files. 🫶

  • Mgdiff.insertForeground: black
  • Mgdiff.insertBackground: orange

These colors are for blocks which have been inserted in one file. 🍊

  • Mgdiff.blankForeground: black
  • Mgdiff.blankBackground: grey66

These colors are for blocks which are for display purposes. 🌫️

  • Mgdiff.selectForeground: black
  • Mgdiff.selectBackground: light slate blue

These colors are for blocks which have been selected by the user. 👑

  • Mgdiff.font: 7x13bold

Font for displaying text blocks. ✨

  • Mgdiff.dragScroll: true

Set to true if scrollbar dragging should cause immediate changes in the viewed text, and false if the view should only change after the scrollbar has been moved.

  • Mgdiff.overview: true

Set to true if the file overview section should appear. 🦋

  • Mgdiff.horzScrollbar: true

Set to true if the horizontal scrollbar should appear. 🌸

  • Mgdiff.linesOfContext: 3

Number of lines that should appear above a difference block gotten to using the Previous or Next commands. Should be greater or equal to zero.

  • Mgdiff.manCommand: (man mgdiff | col -b) 2>&1

The command (or pipeline) used to produce a formatted manual page without escape codes.

  • Mgdiff.diffCommand: diff

The diff(1) compatible command to use for calculating differences between text files.

  • Mgdiff.diffArgs:

The arguments to be provided to the diff command. This resource can also be set via the -args command line option.

  • Mgdiff.quitIfSame: false

If the two files have no differences (as determined by the diff command) then exit immediately without bringing up a window. This resource can also be set to "true" via the -quit command line option. 🚪

  • Mgdiff.filename: (stdin)

mgdiff uses this string to display over a file read from standard input. This resource can also be set via the -file command line option.

😭 DIAGNOSTICS 😭

Returns the exit status generated by the diff command. This is usually 0 for no differences, 1 for some differences and 2 for errors. fr fr, that's the whole mood readout 🎀

👀 SEE ALSO 👀

diff(1), X(1)

💀 RESTRICTIONS 💀

ok so like, the limitations, we're being honest here:

  • Using BDrag in the overview area doesn't work well when drag scrolling is turned off. 💅
  • Doesn't support monochrome displays. no greyscale era for this one 🖤
  • Input lines longer than BUFSIZ (see /usr/include/stdio.h) are silently truncated. the audacity 😭
  • The code for parsing and passing arguments to the diff command assumes arguments are delimited by white space and does not do any quote processing. 🙈
Copyright (c) 1994, Daniel Williams
Copyright (c) 2003, Erik de Castro Lopo

See X(1) for a full statement of rights and permissions. 🫶

👑 AUTHORS 👑

  • Daniel Williams (dan@sass.com)
  • Erik de Castro Lopo (erikd AT mega-nerd DOT com) — added "Save as Left/Right" and saving both and neither sides. ate 💅

🌈 ACKNOWLEDGEMENTS 🌈

To Andrew C. Myers for writing gdiff. the blueprint, the blueprint 🧚💖

and that's the whole page bestie!! 🎀 this was MGDIFF(1x) — the source/version tag MGDIFF(1x) and its date up in the footer, living its little life at the bottom of the man page. go forth, diff things, merge things, be iconic 💜✨

📦 where this page comes from