Update cheatsheets

set

@@ -0,0 +1,29 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# set
+
+> Toggle shell options or set the values of positional parameters.
+> More information: <https://manned.org/set.1posix>.
+
+- Display the names and values of shell variables:
+
+`set`
+
+- Export newly initialized variables to child processes:
+
+`set -a`
+
+- Write formatted messages to `stderr` when jobs finish:
+
+`set -b`
+
+- Write and edit text in the command line with `vi`-like keybindings (e.g. `yy`):
+
+`set -o {{vi}}`
+
+- Exit the shell when (some) commands fail:
+
+`set -e`