Bitcoin debugging followed transactions: Understanding the “Mandatory Script Verify Flag Failed” Error
As a development working with bitcoin transactions, One common challenge is debugging and troubleshooting followed transactions. “Mandatory Script Verify flag failed” and provide guidance on how to resolve it.
The Error: Mandatory Script Verify Fag Failed
Bitcoinj, you might encounter an error indicating that the mandatory script verify flag has failed. This issue is specific to Bitcoin 2.0, which introduced the new followed protocol and its associated verification mechanisms.
To identify the problem, let’s examine the relevant code snippet:
`C
You are main () {
// Create a New Followed Transaction
TX Transaction;
// Set Some Properties (E.G., Hash, ScriptSig)
tx.hash = "your_hash_here";
tx.scriptsig = "your_script_sig_here";
// Create a New Bitcoinj Transaction Object With The Current Options
Bitcoinj.transaction txj = new bitcoinj.transaction (TX);
// Verify the Transaction Signature
if (txj.verifysignature ()) {
// If Verification Succeeds, Broadcast The Transaction
Txj.broadcast ();
} Else {
// Handle the Failure Case
Printf ("Error: Mandatory Script Verify flag Failed \ n");
}
Return 0;
}
“Mandatory script Verify flag failed” indicates that bitcoinj is unable to verify the script signature. This can be due to various reasons, including:
* Missing Script Verification : Ensure that the script used in the transaction has a corresponding verification flag set.
* IncorRect Script Verification Flags : Verify that the mandatory script verify flag (1) is present and correctly configured.
Troubleshooting Steps
To resolve the issue, follow these steps:
1.
`C
scriptpubkey scriptsig = "your_script_sig_here";
.
`C
if (txj.verifysignature ()) {
Txj.broadcast ();
} Else {
// Handle the Failure Case
}
Solution
Verifysignature () BeforeCasting the Transaction. Here's an updated code snippet:
C
You are main () {
// Create a New Followed Transaction
TX Transaction;
tx.hash = "your_hash_here";
tx.scriptsig = "your_script_sig_here"; // Include the Verification Flag
// Verify the Transaction Signature
if (txj.verifysignature ()) {
// If Verification Succeeds, Broadcast The Transaction
Txj.broadcast ();
} Else {
Printf ("Error: Mandatory Script Verify flag Failed \ n");
}
Return 0;
}
The “Mandatory Script Verify Fag Failed” Error when Broadcasting followed transactions using Bitcoinj.