linux - getting error with bash script for env variables -

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• what mean [: -ge: unexpected operator, in bash? 2 answers

i using conditional in bash script

if [ $use_test -eq 1 ]; echo "hello" fi 

where pass use_test environment variables.

if pass env variable shell executes ok if don't have variable this

[: -eq: unexpected operator 

how can fix that

this 1 of matter quotes important; when $use_test not defined, statement expands to:

if [ -eq 1 ]; 

the common fix:

if [ "$use_test" -eq 1 ]; 

...though imply switching string comparison, because -eq break empty string:

if [ "$use_test" = 1 ]; 

but may consider using [[ (which bash builtin) or ${use_test:-0} (which specifies default value).