runuser: add page (#3283)

pages/linux/runuser.md

@@ -0,0 +1,23 @@
+# runuser
+
+> Run commands as a specific user and group without asking for password (needs root privileges).
+
+- Run command as a different user:
+
+`runuser {{user}} -c '{{command}}'`
+
+- Run command as a different user and group:
+
+`runuser {{user}} -g {{group}} -c '{{command}}'`
+
+- Start a login shell as a specific user:
+
+`runuser {{user}} -l`
+
+- Specify a shell for running instead of the default shell (also works for login):
+
+`runuser {{user}} -s {{/bin/sh}}`
+
+- Preserve the entire environment of root (only if `--login` is not specified):
+
+`runuser {{user}} --preserve-environment -c '{{command}}'`