How do I know what COLUMN my cursor is at in Xcode?

Sometimes I want to know what column my cursor is at, so I can see how many characters I have left til the print margin.

This is a common functionality in most IDEs and text editors, but I couldn't find it in Xcode.

Is it possible to enable this or see it somewhere?

What is the left most column in the Xcode text editor known as?

The left-most column in the Code Editor which contains the line numbers is known as the Gutter. Blue arrow-tabs present in the gutter are "breakpoint indicators". Breakpoints are a part of the debugging process that we'll teach you about later. Above: Xcode when encountering a breakpoint.

How do I have two cursors in Xcode?

If you want to add multiple cursors at the same column, instead of wasting time aiming and clicking, you can use the arrow key to navigate. Hold ⌃ – Control and ⇧ - SHIFT then ↑ or ↓ to add cursors to the line above and below your current position. You can deselect a cursor by hit the arrow in the opposite direction.

Open Xcode's Preferences, go to the Text Editing tab, Editing subtab, and check the "Page guide at column: 80" box. That will display a vertical line at 80 columns in the editor.