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README.md

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+# rssfetch
+rssfetch outputs items contained in RSS feeds. You can specify the output
+format with the `-o` flag. For instance, `-o "{{.Title}}"` will only output the
+title of each item.
+
+## Usage
+Run rssfetch with
+```
+rssfetch <feeds> -o <format>
+```
+where `<feeds>` is a list of one or more RSS feeds, and `<format>` is a format
+string.
+
+### Output formatting
+By default, rssfetch will output the title, description, and link of each RSS
+item. To change the output format, use the `-o` flag. The string uses the
+syntax of Go's [text/template](https://pkg.go.dev/text/template) package.
+
+For available fields, see the Item struct of
+[gofeed](https://pkg.go.dev/github.com/mmcdole/gofeed). This includes, but is
+not limited to:
+* `.Title`
+* `.Description`
+* `.Content`
+* `.Link`
+* `.Updated`
+* `.Published`
+
+As an example, running the program as
+```
+rssfetch https://lorem-rss.herokuapp.com/feed -o $'{{.Title}}\n\n\n{{.Link}}\n{{.Published}}\n'
+```
+would output items like the following:
+```
+Lorem ipsum 2024-04-26T03:33:34Z
+
+
+http://example.com/test/1714102414
+Fri, 26 Apr 2024 03:33:34 GMT
+```
+(i.e. the title followed by three new lines, then the link followed by a new
+line, then the publication date followed by a new line.)
+
+*Note that $'string' is a [bash
+feature](https://www.gnu.org/software/bash/manual/html_node/ANSI_002dC-Quoting.html)
+to replace escaped characters like \n, and is not POSIX standard. Other shells
+might need different tricks to use escaped characters.*