Name
if
Synopsis
ifcondition1
thencommands1
[ elifcondition2
thencommands2
] . . . [ elsecommands3
] fi
If condition1 is met, do commands1; otherwise, if condition2 is met, do commands2 ; if neither is met, do commands3. Conditions are often specified with the test and [[ ]] commands. See test and [[ ]] for a full list of conditions, and see additional Examples under : and exit.
Examples
Insert a 0 before numbers less than 10:
if [ $counter -lt 10 ] then number=0$counter else number=$counter fi
Make a directory if it doesn’t exist:
if [ ! -d $dir ]; then mkdir $dir chmod 775 $dir fi
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