From c9a282d08fb1f8670fa328e0e7cdb8801382b88a Mon Sep 17 00:00:00 2001
From: Denis Arh <denis.arh@gmail.com>
Date: Wed, 18 Dec 2013 09:37:27 +0100
Subject: [PATCH] Add example for default value
---
bash.html.markdown | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/bash.html.markdown b/bash.html.markdown
index 1f1c32c0..815290dd 100644
--- a/bash.html.markdown
+++ b/bash.html.markdown
@@ -5,6 +5,7 @@ contributors:
- ["Max Yankov", "https://github.com/golergka"]
- ["Darren Lin", "https://github.com/CogBear"]
- ["Alexandre Medeiros", "http://alemedeiros.sdf.org"]
+ - ["Denis Arh", "https://github.com/darh"]
filename: LearnBash.sh
---
@@ -45,6 +46,10 @@ echo '$VARIABLE'
echo ${VARIABLE/Some/A}
# This will substitute the first occurance of "Some" with "A"
+# Default value for variable
+echo ${FOO:-"DefaultValueIfFOOIsMissingOrEmpty"}
+# This works for null (FOO=), empty string (FOO=""), zero (FOO=0) returns 0
+
# Bultin variables:
# There are some useful builtin variables, like
echo "Last program return value: $?"