ldopen(S)

Syntax

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

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

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

Description

ldaopen- allocates and initializes a new LDFILE structure

The ldopen and ldclose functions provide uniform access to both simple object files and object files that are members of archive files. Thus an archive of common object files can be processed as if it were a series of simple common object files.

If ldptr has the value NULL then ldopen opens filename and allocates and initializes the LDFILE structure, and returns a pointer to the structure to the calling program.

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

The ldopen and ldclose(S) functions work in concert. ldclose returns 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.

If the value of oldptr is not NULL, ldaopen opens filename anew and allocates and initializes 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 ensure that the given file is a common object file or an archived object file.

Example

   /* 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 );

See also

Standards conformance