reverse

Reverses the order of lines (like tac).

Behavior:

• Reads all lines into memory. Large files may exhaust memory.
• Supports plain text and gzipped (.gz) TSV files.

Input:

• Reads from files or standard input.
• Files ending in .gz are transparently decompressed.

Output:

• By default, output is written to standard output.
• Use --outfile to write to a file instead.

Header behavior:

• Supports --header / -H (FirstLine mode) and --header-hash1 (HashLines1 mode). See tva --help-headers for details.
• The header is written once at the top of the output, followed by reversed data lines.

Examples:

1. Reverse a file tva reverse file.tsv

2. Reverse a file, keeping the header at the top tva reverse --header file.tsv

3. Reverse a file with hash comment lines and column names tva reverse --header-hash1 file.tsv