How can `tr` be used to remove trailing spaces?

Actually, it is important to know that tr (translate) cannot be used to remove trailing spaces specifically.

The tr command is designed for character-by-character translation or deletion across the entire file; it does not understand context like "the end of a line."

Why tr isn't the right tool:

• If you use tr -d ' ', it will remove all spaces in the file (turning "Daily Report" into "DailyReport").
• tr cannot distinguish between a space in the middle of a sentence and a space at the end of a line.

How tr IS commonly used with spaces:

While it can't target just the trailing ones, tr is often used to "squeeze" multiple spaces into one:

# This turns multiple spaces into a single space everywhere
cat file.txt | tr -s ' '

Better Alternatives for Trailing Spaces:

Since tr isn't suitable, here is the standard way to do it using a command-line tool that does understand line endings:

1. Using sed (Recommended):

sed 's/ *$//' daily_report.txt

(This looks for a space followed by the end-of-line anchor $).

2. Using perl:

perl -pe 's/\s+$//' daily_report.txt

In summary: use cat -E to see them, and use sed to remove them