chronic, combine, ifdata, ifne, isutf8: add pages (#12114)

* chronic, combine, ifdata, ifne, isutf8: add pages

---------

Co-authored-by: Vitor Henrique <87824454+vitorhcl@users.noreply.github.com>

pages/common/chronic.md

@@ -0,0 +1,16 @@
+# chronic
+
+> Display `stdout` and `stderr` of a command if and only if it fails.
+> More information: <https://joeyh.name/code/moreutils/>.
+
+- Display `stdout` and `stderr` of the specified command if and only if it produces a non-zero exit code or crashes:
+
+`chronic {{command options ...}}`
+
+- Display `stdout` and `stderr` of the specified command if and only if it produces a non-empty `stderr`:
+
+`chronic -e {{command options ...}}`
+
+- Enable [v]erbose mode:
+
+`chronic -v {{command options ...}}`

pages/common/combine.md

@@ -0,0 +1,22 @@
+# combine
+
+> Perform set operations on lines of two files.
+> The order of the output lines is determined by the order of the lines in the first file.
+> See also: `diff`.
+> More information: <https://joeyh.name/code/moreutils/>.
+
+- Output lines that are in both specified files:
+
+`combine {{path/to/file1}} and {{path/to/file2}}`
+
+- Output lines that are in the first but not in the second file:
+
+`combine {{path/to/file1}} not {{path/to/file2}}`
+
+- Output lines that in are in either of the specified files:
+
+`combine {{path/to/file1}} or {{path/to/file2}}`
+
+- Output lines that are in exactly one of the specified files:
+
+`combine {{path/to/file1}} xor {{path/to/file2}}`

pages/common/ifdata.md

@@ -0,0 +1,24 @@
+# ifdata
+
+> Display information about a network interface.
+> More information: <https://joeyh.name/code/moreutils/>.
+
+- Display the whole configuration of the specified interface:
+
+`ifdata -p {{eth0}}`
+
+- Indicate the [e]xistence of the specified interface via the exit code:
+
+`ifdata -e {{eth0}}`
+
+- Display the IPv4 [a]dress and the [n]etmask of the specified interface:
+
+`ifdata -pa -pn {{eth0}}`
+
+- Display the [N]etwork adress, the [b]roadcast adress, and the MTU of the specified interface:
+
+`ifdata -pN -pb -pm {{eth0}}`
+
+- Display help:
+
+`ifdata`

pages/common/ifne.md

@@ -0,0 +1,12 @@
+# ifne
+
+> Run a command depending on the emptyness of `stdin`.
+> More information: <https://joeyh.name/code/moreutils/>.
+
+- Run the specified command if and only if `stdin` is not empty:
+
+`ifne {{command options ...}}`
+
+- Run the specified command if and only if `stdin` is empty, otherwise pass `stdin` to `stdout`:
+
+`ifne -n {{command options ...}}`

pages/common/isutf8.md

@@ -0,0 +1,24 @@
+# isutf8
+
+> Check whether text files contain valid UTF-8.
+> More information: <https://joeyh.name/code/moreutils/>.
+
+- Check whether the specified files contain valid UTF-8:
+
+`isutf8 {{path/to/file1 path/to/file2 ...}}`
+
+- Print errors using multiple lines:
+
+`isutf8 --verbose {{path/to/file1 path/to/file2 ...}}`
+
+- Do not print anything to `stdout`, indicate the result merely with the exit code:
+
+`isutf8 --quiet {{path/to/file1 path/to/file2 ...}}`
+
+- Only print the names of the files containing invalid UTF-8:
+
+`isutf8 --list {{path/to/file1 path/to/file2 ...}}`
+
+- Same as `--list` but inverted, i.e., only print the names of the files containing valid UTF-8:
+
+`isutf8 --invert {{path/to/file1 path/to/file2 ...}}`