How to remove trailing spaces?

While the cat command is great for seeing trailing spaces (using the -E option), it doesn't have a built-in function to remove them. In Linux, we typically use other tools like sed or tr for this task.

Here are the most common ways to remove trailing spaces:

1. Using sed (The most common way)

The sed command is a powerful stream editor. You can use it to find spaces at the end of a line and "replace" them with nothing.

sed 's/[[:space:]]*$//' daily_report.txt

• s/: substitute
• [[:space:]]*: any number of spaces or tabs
• $: at the end of the line
• //: replace with nothing

If you want to save the changes back to the file, add the -i (in-place) flag:

sed -i 's/[[:space:]]*$//' daily_report.txt

2. Using awk

awk can also trim trailing whitespace by redefining the line:

awk '{sub(/[ \t]+$/, ""); print}' daily_report.txt

3. Using your IDE

Since you are using the LabEx WebIDE (VSCode-like interface), you can also do this without commands:

1. Open the file in the editor.
2. Press Ctrl+Shift+P (or Cmd+Shift+P on Mac).
3. Type "Trim Trailing Whitespace" and press Enter.

Pro-tip: After you run one of the commands above, try running cat -E daily_report.txt again. You will notice the $ symbol now sits directly after the last character of text!