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Use proper string comparison syntax

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Matteo Baglini 2016-01-12 00:32:03 +01:00
parent 7e069bef5d
commit f94dea8379
1 changed files with 4 additions and 4 deletions
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8
bash.html.markdown
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@ -83,7 +83,7 @@ echo Hello, $Name!
# We have the usual if structure:
# use 'man test' for more info about conditionals
if [ $Name -ne $USER ]
if [ $Name != $USER ]
then
echo "Your name isn't your username"
else
@ -91,12 +91,12 @@ else
fi
# NOTE: if $Name is empty, bash sees the above condition as:
if [ -ne $USER ]
if [ != $USER ]
# which is invalid syntax
# so the "safe" way to use potentially empty variables in bash is:
if [ "$Name" -ne $USER ] ...
if [ "$Name" != $USER ] ...
# which, when $Name is empty, is seen by bash as:
if [ "" -ne $USER ] ...
if [ "" != $USER ] ...
# which works as expected
# There is also conditional execution