52.2 Truncation

When a line of text extends beyond the right edge of a window, the line can either be truncated or continued on the next line. When a line is truncated, this is normally shown with a ‘\’ in the rightmost column of the window on X displays, and with a ‘$’ on TTY devices. When a line is continued or “wrapped” onto the next line, this is shown with a curved arrow in the rightmost column of the window (or with a ‘\’ on TTY devices). The additional screen lines used to display a long text line are called continuation lines.

Normally, whenever line truncation is in effect for a particular window, a horizontal scrollbar is displayed in that window if the device supports scrollbars. See Scrollbars.

Note that continuation is different from filling; continuation happens on the screen only, not in the buffer contents, and it breaks a line precisely at the right margin, not at a word boundary. See Filling.

User Option: truncate-lines

This buffer-local variable controls how SXEmacs displays lines that extend beyond the right edge of the window. If it is non-nil, then SXEmacs does not display continuation lines; rather each line of text occupies exactly one screen line, and a backslash appears at the edge of any line that extends to or beyond the edge of the window. The default is nil.

If the variable truncate-partial-width-windows is non-nil, then truncation is always used for side-by-side windows (within one frame) regardless of the value of truncate-lines.

User Option: default-truncate-lines

This variable is the default value for truncate-lines, for buffers that do not have local values for it.

User Option: truncate-partial-width-windows

This variable controls display of lines that extend beyond the right edge of the window, in side-by-side windows (see Splitting Windows). If it is non-nil, these lines are truncated; otherwise, truncate-lines says what to do with them.

The backslash and curved arrow used to indicate truncated or continued lines are only defaults, and can be changed. These images are actually glyphs (see Glyphs). SXEmacs provides a great deal of flexibility in how glyphs can be controlled.

For details, Redisplay Glyphs.