Evaluate expressions.

Synopsis

expr EXPRESSION

Description

Evaluates EXPRESSION and prints the result. Supports arithmetic (+ - \* / %), comparison, and string operators, matching the POSIX expr utility. Each operator and operand must be a separate argument.

Examples

$ expr 3 + 4

Print 7.

$ x=$(expr $x + 1)

Increment a shell variable.

$ P

r

Notes

Operators like *, <, > must usually be escaped or quoted to avoid shell interpretation. Prefer $(( )) arithmetic expansion in bash for simple arithmetic; expr exists mainly for POSIX-shell portability.

See Also

bash, awk