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AcuSolve User-Defined Functions Manual
Customization of AcuSolve allowing you to customize certain capabilities of the solver.
Client/Server Routines
These routines are accessible only by multiplier function and mesh motion user functions.
udfWritePipe()
Write (send) a message to an external program.

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AcuSolve Training Manual
Introduction of background knowledge regarding flow physics and CFD as well as detailed information about the use of AcuSolve and what specific options do.
AcuSolve Validation Manual
Collection of AcuSolve simulation cases for which results are compared against analytical or experimental results to demonstrate the accuracy of AcuSolve results.
AcuSolve Command Reference Manual
AcuSolve command descriptions and corresponding examples.
AcuSolve Programs Reference Manual
AcuSolve utility programs covering preparatory and post-processing as well as user-defined functions and utility scripts.
AcuSolve User-Defined Functions Manual
Customization of AcuSolve allowing you to customize certain capabilities of the solver.
- Input File
  To access a user-defined function in AcuSolve, you must reference it in the input file.
- Function Format
  A user-defined function has the following form (in C).
- Compile, Link and Run
  In order for the solver to access the user-defined functions, the functions must be compiled and linked into a shared library. The script acuMakeLib (for Linux) and acuMakeDll (for Windows) may be used for this purpose.
- Support Routines
  Within a user-defined function or an external output code data may be accessed through support routines. These routines provide flexibility, longevity, efficiency and the ability to check for run-time errors.
- Basic Routines
  These routines are accessible by all user functions, and by external output codes.
- Client/Server Routines
  These routines are accessible only by multiplier function and mesh motion user functions.
  - udfOpenPipe()
    Open a pipe to an external program.
  - udfOpenPipePrim()
    Open a pipe to an external program from main processor.
  - udfWritePipe()
    Write (send) a message to an external program.
  - udfReadPipe()
    Read (receive) a line of data from an external program.
- Global Routines
  These routines are accessible by all user functions, and by external output codes.
- Element Routines
  These routines are accessible only by the Body Force, Material Model and Component Model user functions, and by external output codes.
- Element Boundary Condition Routines
  These support routines are accessible only by the Element Boundary Condition user functions, and by external output codes.
- Nodal Boundary Condition Routines
  These support routines are accessible only by the Nodal Boundary Condition user functions.
- Nodal Initial Condition Routines
  These support routines are accessible only by the Nodal Initial Condition user functions.
- Periodic Boundary Condition Routines
  These support routines are accessible only by the Periodic Boundary Condition user functions.
- Subdomain Routines
  These support routines are accessible only within external output codes.
AcuTrace Command Reference Manual
Commands of AcuTrace, a particle tracer that runs as a post-processor to or a co-processor with AcuSolve.
AcuTrace User-Defined Functions Manual
Instructions to define additional solution quantities of AcuTrace called user equations.
AcuReport Reference Manual
Instruction of the AcuReport tool, a standalone post-processor batch tool used to generate a report from an AcuSolve solution database.
AcuSolve Surface Processing

udfWritePipe()

Write (send) a message to an external program.

Syntax

udfWritePipe( udfHd, format, ... ) ;

Type

AcuSolve User-Defined Function Client

Parameters

udfHd: The opaque handle (pointer) which was passed to the user function.
format (string): C printf() format.
... (vararg): List of C variable.

Return Value

None

Description

This routine writes (sends) a message to the pipe opened by udfOpenPipe or udfOpenPipePrim. The argument list is the same as that of fprintf(), except that here udfHd takes the place of the file descriptor. For example,

udfWritePipe( udfHd, "pressure= %.16g", -trac[0] ) ;

Errors

This routine expects a valid udfHd.
May only be called from a multiplier function or mesh motion user-defined function.