.TH NSObjectFileImage 3 "April 24, 2000" "Apple Computer, Inc."
.SH NAME
NSObjectFileImage \- programmatic interface for working with Mach-O files
.SH SYNOPSIS
.nf
.PP
#include <mach-o/dyld.h>
.sp .5
extern NSObjectFileImageReturnCode NSCreateObjectFileImageFromFile(
	const char *pathName,
	NSObjectFileImage *objectFileImage);
.sp .5
extern NSObjectFileImageReturnCode NSCreateCoreFileImageFromFile(
	const char *pathName,
	NSObjectFileImage *objectFileImage);
.if
.SH "FUTURE SYNOPSIS"
.nf
.PP
extern NSObjectFileImageReturnCode NSCreateObjectFileImageFromMemory(
	void *address,
	unsigned long size, 
	NSObjectFileImage *objectFileImage);
.sp .5
extern enum DYLD_BOOL NSDestroyObjectFileImage(
	NSObjectFileImage objectFileImage);
.sp .5
extern unsigned long NSSymbolDefinitionCountInObjectFileImage(
	NSObjectFileImage objectFileImage);
.sp .5
extern const char * NSSymbolDefinitionNameInObjectFileImage(
	NSObjectFileImage objectFileImage,
	unsigned long ordinal);
.sp .5
extern unsigned long NSSymbolReferenceCountInObjectFileImage(
	NSObjectFileImage objectFileImage);
.sp .5
extern const char * NSSymbolReferenceNameInObjectFileImage(
	NSObjectFileImage objectFileImage,
	unsigned long ordinal,
	enum DYLD_BOOL *tentative_definition); /* can be NULL */
.sp .5
extern enum DYLD_BOOL NSIsSymbolDefinedInObjectFileImage(
	NSObjectFileImage objectFileImage,
	const char *symbolName);
.sp .5
extern void * NSGetSectionDataInObjectFileImage(
	NSObjectFileImage objectFileImage,
	const char *segmentName,
	const char *sectionName);
.fi
.SH DESCRIPTION
.PP
These routines are the programmatic interface for working with Mach-O files.
They bring the Mach-O file into memory and the API allows the file to
be inspected or loaded into the program.  On creation of an object file image
it is checked to insure it is a valid format and it is compatible with the host
machine's cpu architecture.
.PP
.I NSCreateObjectFileImageFromFile
takes the parameter
.I pathName
as the path name to the file name in the file system and creates and returns
an NSObjectFileImage.  Currently only
.SM MH_BUNDLE
files can be used with
.I NSCreateObjectFileImageFromFile
which can then be loaded into the program using
.IR NSLinkModule (3).
If the file is valid an NSObjectFileImage is returned and the return code is
NSObjectFileImageSuccess.
.PP
.I NSCreateCoreFileImageFromFile
takes the parameter
.I pathName
as the path name to a core file in the file system and creates and returns
an NSObjectFileImage.  This NSObjectFileImage can then can be loaded into a
task with
.IR _dyld_debug_task_from_core (3)
to determine what libraries were loaded and which modules were linked.
.SH RETURN CODES
The API's that create NSObjectFileImage's return an NSObjectFileImageReturnCode
with the following possible values:
.TP
.B NSObjectFileImageSuccess
Indicates the API was successful and it returned a valid NSObjectFileImage for
the host machine's cpu architecture.
.TP
.B NSObjectFileImageFailure
Indicates the API failed and no NSObjectFileImage was returned.  If this is
returned an error message is printed on stderr as to the reason for the 
failure.
.TP
.B NSObjectFileImageInappropriateFile
Indicates the API failed because the file passed to it was not an appropriate
type of object file.
.TP
.B NSObjectFileImageArch
Indicates the API failed because the host machine's cpu architecture could not
be found in the file.
.TP
.B NSObjectFileImageFormat
Indicates the API failed because the Mach-O format was malformed.  If this is
returned an error message is printed on stderr as to the format error.
.TP
.B NSObjectFileImageAccess
Indicates the API failed because the file could not be accessed.
.SH ALSO SEE
NSModule(3), dyld(3)