update folders

snipplets/code/Bash/command_exists.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+if ! [ -x "$(command -v git)" ]; then
+    echo 'Error: git is not installed.' >&2
+    exit 1
+fi
+
+if ! command -v crystal &> /dev/null
+then
+    echo "<the_command> could not be found"
+    exit
+fi

snipplets/code/Bash/irc_logger.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+
+# https://linuxconcept.com/making-a-simple-irc-chat-bot-logger-using-bash-script/
+
+nick="blb$$"
+channel=admin
+server=iiiypuk.me
+config=/tmp/irclog
+[ -n "$1" ] && channel=$1
+[ -n "$2" ] && server=$2
+config="${config}_${channel}"
+echo "NICK $nick" > $config
+echo "USER $nick +i * :$0" >> $config
+echo "JOIN #$channel" >> $config
+trap "rm -f $config;exit 0" INT TERM EXIT
+tail -f $config | nc $server 6667 | while read MESSAGE
+do
+    case "$MESSAGE" in
+        PING*) echo "PONG${MESSAGE#PING}" >> $config;; *QUIT*) ;;
+        *PART*) ;;
+        *JOIN*) ;;
+        *NICK*) ;;
+        *PRIVMSG*) echo "${MESSAGE}" | sed -nr "s/^:([^!]+).*PRIVMSG[^:]+:(.*)/[$(date '+%R')] \1> \2/p" >> $config;;
+        *) echo "${MESSAGE}";;
+    esac
+done

snipplets/code/Bash/unix-socket-server.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+# TCP
+#coproc nc -l localhost 3000
+
+# UnixSocket
+coproc nc -l -U ./app.sock
+
+while read -r cmd; do
+  case $cmd in
+    d) date ;;
+    q) break ;;
+    *) echo 'Try again?'
+  esac
+done <&"${COPROC[0]}" >&"${COPROC[1]}"
+
+kill "$COPROC_PID"