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| OPENMP API Specification: Version 5.0 November 2018

6.12  OMP_DISPLAY_ENV

The OMP_DISPLAY_ENV environment variable instructs the runtime to display the OpenMP version number and the value of the ICVs associated with the environment variables described in Chapter 6, as name = value pairs. The runtime displays this information once, after processing the environment variables and before any user calls to change the ICV values by runtime routines defined in Chapter 3.

The value of the OMP_DISPLAY_ENV environment variable may be set to one of these values:

TRUE | FALSE | VERBOSE

The TRUE value instructs the runtime to display the OpenMP version number defined by the _OPENMP version macro (or the openmp_version Fortran parameter) value and the initial ICV values for the environment variables listed in Chapter 6. The VERBOSE value indicates that the runtime may also display the values of runtime variables that may be modified by vendor-specific environment variables. The runtime does not display any information when the OMP_DISPLAY_ENV environment variable is FALSE or undefined. For all values of the environment variable other than TRUE, FALSE, and VERBOSE, the displayed information is unspecified.

The display begins with "OPENMP DISPLAY ENVIRONMENT BEGIN", followed by the _OPENMP version macro (or the openmp_version Fortran parameter) value and ICV values, in the format NAME ’=’ VALUE. NAME corresponds to the macro or environment variable name, optionally prepended by a bracketed device-type. VALUE corresponds to the value of the macro or ICV associated with this environment variable. Values are enclosed in single quotes. The display is terminated with "OPENMP DISPLAY ENVIRONMENT END".

For the OMP_NESTED environment variable, the printed value is true if the max-active-levels-var ICV is initialized to a value greater than 1; otherwise the printed value is false.

Example:  

 
% setenv OMP_DISPLAY_ENV TRUE  

The above example causes an OpenMP implementation to generate output of the following form:  

 
OPENMP DISPLAY ENVIRONMENT BEGIN 
  _OPENMP=’201811’ 
  [host] OMP_SCHEDULE=’GUIDED,4’ 
  [host] OMP_NUM_THREADS=’4,3,2’ 
  [device] OMP_NUM_THREADS=’2’ 
  [host,device] OMP_DYNAMIC=’TRUE 
  [host] OMP_PLACES=’{0:4},{4:4},{8:4},{12:4}’ 
  ... 
OPENMP DISPLAY ENVIRONMENT END