LDOPEN(3X)

NAME
ldopen, ldaopen - open a COFF file for reading

SYNOPSIS
#include <stdio.h>
#include <filehdr.h>
#include <ldfcn.h>

LDFILE *ldopen (filename, ldptr)
char *filename;
LDFILE *ldptr;

LDFILE *ldaopen (filename, oldptr)
char *filename;
LDFILE *oldptr;

AVAILABILITY

Available only on Sun 386i systems running a SunOS 4.0.x release or earlier. Not a SunOS 4.1 release feature.

DESCRIPTION

ldopen() and ldclose(3X) are designed to provide uniform access to both simple object files and object files that are members of archive files. Thus an archive of COFF files can be processed as if it were a series of simple COFF files.

If ldptr has the value NULL, then ldopen() will open filename and allocate and initialize the LDFILE structure, and return a pointer to the structure to the calling program.

If ldptr is valid and if TYPE(ldptr) is the archive magic number, ldopen() will reinitialize the LDFILE structure for the next archive member of filename.

ldopen() and ldclose(3X) are designed to work in concert. ldclose will return FAILURE only when TYPE(ldptr) is the archive magic number and there is another file in the archive to be processed. Only then should ldopen() be called with the current value of ldptr. In all other cases, in particular whenever a new filename is opened, ldopen() should be called with a NULL ldptr argument.

The following is a prototype for the use of ldopen() and ldclose(3X).

    /* for each filename to be processed */

    ldptr = NULL;
    do
    {
    	if ( (ldptr = ldopen(filename, ldptr)) != NULL )
    	{
    		/* check magic number */
    		/* process the file */
    	}
    } while (ldclose(ldptr) == FAILURE );

If the value of oldptr is not NULL, ldaopen() will open filename anew and allocate and initialize a new LDFILE structure, copying the TYPE, OFFSET, and HEADER" fields from oldptr. ldaopen() returns a pointer to the new LDFILE structure. This new pointer is independent of the old pointer, oldptr. The two pointers may be used concurrently to read separate parts of the object file. For example, one pointer may be used to step sequentially through the relocation information, while the other is used to read indexed symbol table entries.

Both ldopen() and ldaopen() open filename for reading. Both functions return NULL if filename cannot be opened, or if memory for the LDFILE structure cannot be allocated. A successful open does not insure that the given file is a COFF file or an archived object file.

The program must be loaded with the object file access routine library libld.a.

SEE ALSO
fopen(3V), ldclose(3X), ldfcn(3)