Inside Macintosh: Operating System Utilities /

Chapter 1 - Gestalt Manager / Gestalt Manager Reference

Gestalt Manager Routines / Getting Information About the Operating Environment

SysEnvirons

You can use the SysEnvirons function when you need information about the operating environment and the Gestalt function is not available.

FUNCTION SysEnvirons (versionRequested: Integer; 
                      VAR theWorld: SysEnvRec): OSErr;

versionRequested

The version number of SysEnvirons you expect.

theWorld

A system environment record.

DESCRIPTION

The SysEnvirons function fills in a system environment record identified by the variable parameter theWorld. It returns a result code.

You use the versionRequested parameter to tell SysEnvirons which version of the system environment record you're prepared to receive. This chapter documents version 2, which contains the same fields as version 1 but recognizes a more complete set of descriptive constants. Apple will raise the SysEnvirons version number in the future only if the record structure changes. You can trust any future revision to return the version 2 record if you request it, although the record might contain whatever constants are then current. To request the most recent version, you can use the constant curSysEnvVers:

CONST
   curSysEnvVers = 2;

ASSEMBLY-LANGUAGE INFORMATION

The registers on entry and exit for the SysEnvirons function are

Registers on entry
A0	Address of a system environment record
D0	Version requested

Registers on exit
A0	Address of a system environment record
D0	Result code

RESULT CODES

noErr	0	No error
envNotPresent	-5500	SysEnvirons trap not present
envBadVers	-5501	Nonpositive version number passed
envVersTooBig	-5502	Requested version of SysEnvirons not available

SEE ALSO

See "The System Environment Record" beginning on page 1-28 for a detailed description of the system environment record.