void printf(string format, ...)
Like the trace() action, the printf() action traces D expressions. However, the printf() action lets you control formatting in ways similar to the printf(3C) function. Like the printf function, the parameters consists of a format string followed by a variable number of arguments. By default, the arguments are traced to the directed buffer. The arguments are later formatted for output by the dtrace command according to the specified format string.
For more information on the printf() action, see Chapter 12, Output Formatting, in Solaris Dynamic Tracing Guide.