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/*
* Linux DTrace
* Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
#!/usr/sbin/dtrace -s
#pragma D option quiet
/*
* SYNOPSIS
* sudo ./306actions-speculations.d
*
* DESCRIPTION
* In DTrace, one can write output speculatively, deciding at a
* later time whether to commit or discard the speculative output.
*/
#pragma D option nspec=2
BEGIN
{
/* create two speculations */
s1 = speculation();
s2 = speculation();
}
BEGIN
{
/* the clause has "speculate()" before data recording */
speculate(s1);
printf("one\n");
}
BEGIN
{
speculate(s2);
printf("two\n");
}
BEGIN
{
speculate(s1);
printf("three\n");
}
BEGIN
{
speculate(s2);
printf("four\n");
}
BEGIN
{
commit(s1); /* commit "one" "three" output */
discard(s2); /* discard "two" "four" output */
}
BEGIN
{
/* cannot be in same clause as commit/discard */
exit(0);
}
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