SF(1)

NAME
sf - An interactive file viewer written for Unix-like systems.

OVERVIEW

The sf (or Show File) application displays a text file through a logical window which can be moved forward and backward on the file. The utility is invoked by using the sf command or through the show application.

If the sf application is invoked without specifiing a file name, the following prompt requesting a file is displayed.

Show File - Enter pathname:

The screen format is very simple with a command line at the top of the screen, a display window consisting of the middle rows of the screen, and a file identification line at the bottom of the window. The identification line gives the line and column number of the top left character in the window. An example of the command line and information line is given below.

F1-Down, F2-Up, F3-Top, F4-Bottom, Config, Find, Help, Position, Quit, Wrap-on

File = /home/robert/sf.txt Top = 1:1

The end of the file is indicated by a "*eof" line displayed in the file window after the last line of the file.

COMMAND LINE ARGUMENTS

-w, --wrap Enables line wrapping.

--theme=[THEME]: Color themes. Passsing this argument
    without an option will display available themes.

    --settings-menu Launch sf directly into the settings menu.

    --help: Displays help message, then exits.

    --version: Displays program version, then exits.

COMMANDS

The sf application provides functions to move the window up or down on the file being displayed. These functions are invoked by function keys specified before the function name. Commands are provided to position the window to a spesific line of the file and to quit the utility. These commands are invoked by using the first letter of the command name. Each of the commands and functions are described below.

F1, PgDn
    Move the file window down or forward on the file by the size of the display to show the next section of the file.

F2, PgUp
    Move the file window up or backward on the file by the size of the display to show the previous section of the file.

F3  Top of File - Position the file window to the first line of the file.

F4  Bottom of File - Position the file window to the last line of the file.

    Config Launches sf's configuration menu. From here, all aspects of sf can be configured, and settings saved so they will persist between sessions. Further information can be found in the configuring sf section.

Find
    Searches for a string provided in the form of a Regex. Case sensitivity is requested by the following prompt, afterwards the user is asked to input the string to search. To abort at this prompt, the ESC key must be used.

    Ignore-case Case-sensitive (enter = I)

    Following this selection, one of the following prompts will be displayed:

    Match Case - Enter string:

    Ignore Case - Enter string:

    After a search has been made, the keybinding CTRL + F will repeat the search to find further occurrences.

Help
    Launches the man pages for sf.

Position
    Position the file window to a specific line of the file or relative from the current file position. The new file postion is requested by the following prompt.

    Position relative (+num || -num) or absolute (num):

    If a number without a plus "+" or minus "-" sign is specified, then the file window is moved to the specified line number if it exists. If a number with a plus "+" sign is specified, then the file window is moved down or forward by the specified number of lines. Otherwise if a number with a minus "-" sign is specified then the file window is moved up or backward by the specified number of lines.

Quit
    Terminate the sf application and return to the utility which invoked it, or the user's terminal.

Wrap-on, Wrap-off
    Toggles line wrapping on or off. When enabled, the information line only shows the line number.

Home
    Position the file window to the first column of the file.

End Position the file window to the last column of the file.

CONFIGURING SF

sf features an inbuilt configuration menu where the user can tweak the default settings. It is accessed using the Config command.

The following screen is displayed.

SF Settings Menu - Quit, Revert, Save
   [ ] Enable text wrapping

The menu is made up of toggle switches. When active, the switch will display [*], when inactive [ ] is displayed. To toggle a value, press SPACE when the cursor is highlighed over a specific item.

The following commands can be used within this menu.

Quit Applies changes and either returns to the previous screen.

Revert Reverts settings to their original value from when the settings menu was invoked.

Save Saves settings for future sessions.

AUTHOR
Robert Ian Hawdon

COPYRIGHT
2024, Robert Ian Hawdon