I'm aware of these posts

How do you sign an verify a message in javascript proving you own an Ethereum address?

How does one properly use ecrecover to verify Ethereum signatures?

I'd like to sign a message and then verify it. I use the following command line in the geth terminal.

var msg = web3.sha3('Schoolbus')
var signature = web3.eth.sign(web3.eth.accounts[0], msg)
var r = signature.slice(0, 66)
var s = '0x' + signature.slice(66, 130)
var v = '0x' + signature.slice(130, 132)
v = web3.toDecimal(v)

Then I use the smart contract below, and call:

   call_ecover(r, s,  v, msg)

But what i get is: 0x0000000000000000000000000000000000000000

 pragma solidity ^0.5.0;
 contract Call_verify{

  function call_ecover(bytes32 r, bytes32 s, uint8 v, 
  bytes32 hash)external pure returns (address){
  bytes memory prefix = "\x19Ethereum Signed 
  Message:\n32";    
  bytes32 prefixedHash = 
  keccak256(abi.encodePacked(prefix,hash));  
  return ecrecover(prefixedHash, v, r, s);    
  } 
 
}

Note that I'm using compiler version 0.5.3 on remix.

Question: Why cannot I get the return value of ecrecover() function in my contract? Am I missing anything?

I'm aware of these posts

How do you sign an verify a message in javascript proving you own an Ethereum address?

How does one properly use ecrecover to verify Ethereum signatures?

I'd like to sign a message and then verify it. I use the following command line in the geth terminal.

var msg = web3.sha3('Schoolbus')
var signature = web3.eth.sign(web3.eth.accounts[0], msg)
var r = signature.slice(0, 66)
var s = '0x' + signature.slice(66, 130)
var v = '0x' + signature.slice(130, 132)
v = web3.toDecimal(v)

Then I use the smart contract below, and call:

   call_ecover(r, s,  v, msg)

But what i get is: 0x0000000000000000000000000000000000000000

 pragma solidity ^0.5.0;
 contract Call_verify{

  function call_ecover(bytes32 r, bytes32 s, uint8 v, 
  bytes32 hash)external pure returns (address){
  bytes memory prefix = "\x19Ethereum Signed 
  Message:\n32";    
  bytes32 prefixedHash = 
  keccak256(abi.encodePacked(prefix,hash));  
  return ecrecover(prefixedHash, v, r, s);    
  } 
 
}

Note that I'm using compiler version 0.5.3 on remix.

Question: Why cannot I get the return value of ecrecover() function in my contract? Am I missing anything?

I'm aware of these posts

How do you sign an verify a message in javascript proving you own an Ethereum address?

How does one properly use ecrecover to verify Ethereum signatures?

I'd like to sign a message and then verify it. I use the following command line in the geth terminal.

var msg = web3.sha3('Schoolbus')
var signature = web3.eth.sign(web3.eth.accounts[0], msg)
var r = signature.slice(0, 66)
var s = '0x' + signature.slice(66, 130)
var v = '0x' + signature.slice(130, 132)
v = web3.toDecimal(v)

Then I use the smart contract below, and call:

   call_ecover(r, s,  v, msg)

But what i get is: 0x0000000000000000000000000000000000000000

 pragma solidity ^0.5.0;
 contract Call_verify{

  function call_ecover(bytes32 r, bytes32 s, uint8 v, 
  bytes32 hash)external pure returns (address){
  bytes memory prefix = "\x19Ethereum Signed 
  Message:\n32";    
  bytes32 prefixedHash = 
  keccak256(abi.encodePacked(prefix,hash));  
  return ecrecover(prefixedHash, v, r, s);    
  } 
 
}

Note that I'm using compiler version 0.5.3 on remix.

Question: Where cannot get the return value of ecrecover() function in my contract? Am I missing anything?

I'm aware of these posts

How do you sign an verify a message in javascript proving you own an Ethereum address?

How does one properly use ecrecover to verify Ethereum signatures?

I'd like to sign a message and then verify it. I use the following command line in the geth terminal.

var msg = web3.sha3('Schoolbus')
var signature = web3.eth.sign(web3.eth.accounts[0], msg)
var r = signature.slice(0, 66)
var s = '0x' + signature.slice(66, 130)
var v = '0x' + signature.slice(130, 132)
v = web3.toDecimal(v)

Then I use the smart contract below, and call:

   call_ecover(r, s,  v, msg)

But what i get is: 0x0000000000000000000000000000000000000000

 pragma solidity ^0.5.0;
 contract Call_verify{

  function call_ecover(bytes32 r, bytes32 s, uint8 v, 
  bytes32 hash)external pure returns (address){
  bytes memory prefix = "\x19Ethereum Signed 
  Message:\n32";    
  bytes32 prefixedHash = 
  keccak256(abi.encodePacked(prefix,hash));  
  return ecrecover(prefixedHash, v, r, s);    
  } 
 
}

Note that I'm using compiler version 0.5.3 on remix.

Question: Why cannot I get the return value of ecrecover() function in my contract? Am I missing anything?