ch01/

Dup1 prints the text of each line that appears more than once in the standard input, preceded by its count.

Dup2 prints the count and text of lines that appear more than once in the input.

Echo1 prints its command-line arguments.

Echo2 prints its command-line arguments.

Echo3 prints its command-line arguments.

Echo4 prints its command-line arguments.

Exercise 1.1: Modify the echo program to also print os.Args[0], the name of the command that invoked it.

Exercise 1.10: Find a web site that produces a large amount of data.

Exercise 1.2: Modify the echo program to print the index and value of each of its arguments, one per line.

Exercise 1.3: Experiment to measure the difference in running time between our potentially inefficient versions and the one that uses strings.Join.

Exercise 1.4: Modify dup2 to print the names of all files in which each duplicated line occurs.

Exercise 1.5: Change the Lissajous program’s color palette to green on black, for added authenticity.

Exercise 1.6: Modify the Lissajous program to produce images in multiple colors by adding more values to palette and then displaying them by changing the third argument of SetColorIndex in some interesting way.

Exercise 1.7: The function call io.Copy(dst, src) reads from src and writes to dst.

Exercise 1.8: Modify fetch to add the prefix http:// to each argument URL if it is missing.

Exercise 1.9: Modify fetch to also print the HTTP status code, found in resp.Status.

Fetch prints the content found at a URL.

Fetchall fetches URLs in parallel and reports their times and sizes.

Lissajous generates GIF animations of random Lissajous figures.