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How do I fix error unary operator expected?

How do I fix error unary operator expected?

$ bash -xv ./ #! /bin/bash read -p “Enter the input: ” num1 + read -p ‘Enter the input: ‘ num1 Enter the input: if [ $num1 -eq 1 ] then echo “Number entered is 1” else echo “Not equal to One !!” fi + ‘[‘ -eq 1 ‘]’ ./ line 3: [: -eq: unary operator expected + echo ‘Not equal to One !!

Is An unary operator?

…and != is not a unary operator (that is, one capable of taking only a single argument).

Which is not unary operator?


Operator Explanation
Unary negation ( – ) Tries to convert the operand into a number and negates after
Increment ( ++ ) Adds one to its operand
Decrement ( — ) Decrements by one from its operand
Logical NOT ( ! ) Converts to boolean value then negates it

What is unary operators in Java?

Java unary operators are the types that need only one operand to perform any operation like increment, decrement, negation, etc. It consists of various arithmetic, logical and other operators that operate on a single operand.

What is operator in bash?

Bash has a large set of logical operators that can be used in conditional expressions. There are three types of operators: file, numeric, and non-numeric operators. Each operator returns true (0) if the condition is met and false (1) if the condition is not met.

Which unary operator is expected?

What is the Bash Unary Operator Expected error? It’s an error that occurs when Bash identifies a line in your script that contains a binary operator that is not applied to two arguments. When this happens Bash assumes that you want to use a unary operator instead and raises the Unary Operator Expected error.

What is unary operator bash?

The bash message unary operator expected. means that you do a comparison where one site is empty for example if [ $name = “foo” ] and $name is empty. Then the bash shell internally replaces $name by an empty string and it will be interpreted as if [ = “foo” ] and this is not a valid expression.

Which is correct example of unary operator?

Which is the correct example of a unary operator? Explanation: &, == and / requires two operands whereas — requires only one operand, in general, it decreases the value of operand by 1.

Which exception is thrown by read () method?

Which exception is thrown by read() method? Explanation: read method throws IOException.

What is increment and decrement in Java?

In Java, the increment unary operator increases the value of the variable by one while the decrement unary operator decreases the value of the variable by one. Both update the value of the operand to its new value. The increment and decrement unary operators have two forms, which are, prefix and postfix.

Do while loops bash?

There is no do-while loop in bash. To execute a command first then run the loop, you must either execute the command once before the loop or use an infinite loop with a break condition.

What are bad operand types for binary operator?

Example: Producing the error by using if condition. Just like above,we will produce the error first before moving on to the solution.

  • Explanation: The cause of this error is that (x/2) is a numeric expression that will return an integer value. We all know&&is the logical AND operator.
  • Solution: That’s all for today.
  • What is mean by unary operator expexcted?


  • Decrement: −−$x,$x −−
  • Positive:+$x
  • Negative: −$x
  • Logical negation: !$x
  • Invoke in current scope: .$x
  • Invoke in new scope:&$x
  • Cast:[type-name]cast-expression
  • Cast:+$x
  • Array:,$array
  • What is an unary operation?

    In mathematics, a unary operation is an operation with only one operand, i.e. a single input. This is in contrast to binary operations, which use two operands. An example is the function f: A → A, where A is a set. Is addition a unary operations? Unary operations involve only one value, such as negation and trigonometric functions.

    What are unary, binary, and ternary operators in C?

    – Unary operators expect one (1) operand. – Binary operators expect two (2) operands. – Ternary operators expect three (3) operands.

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