expr
Evaluate expressions and manipulate strings. tldr-pages
On several platforms
Several platforms
Get the length of a specific string
expr length "string"IdentifyGet the substring of a string with a specific length
expr substr "string" from lengthIdentifyMatch a specific substring against an anchored pattern
expr match "string" 'pattern'IdentifyGet the first char position from a specific set in a string
expr index "string" "chars"IdentifyCalculate a specific mathematic expression
expr expression1 + expression2IdentifyGet the first expression if its value is non-zero and not null otherwise get the second one
expr expression1 \| expression2IdentifyGet the first expression if both expressions are non-zero and not null otherwise get zero
expr expression1 \& expression2Identify