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ldopen(3)
NAME
  ldopen, ldaopen - open a common object file for reading

LIBRARY
  libmld.a

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

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

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

  ldreadst (ldptr, flags)
  LDFILE *ldptr;
  int flags;

DESCRIPTION
  The ldopen and ldclose(3) routines provide uniform access to simple object
  files and to object files that are members of archive files.	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, ldopen opens filename, allocates and
  initializes the LDFILE structure, and returns a pointer to the structure to
  the calling program.

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

  ldopen and ldclose 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, and particularly when 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:

       /* 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 opens filename anew and
  allocates and initializes a new LDFILE structure, copying the 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 can be
  used concurrently to read separate parts of the object file.	For example,
  one pointer can be used to step sequentially through the relocation
  information while the other is used to read indexed symbol table entries.

  The ldopen function and ldaopen open filename for reading.  If filename
  cannot be opened or if memory for the LDFILE structure cannot be allocated,
  both functions return NULL. A successful open does not ensure that the
  given file is a common object file or an archived object file.

  The ldopen function causes the symbol table header and file descriptor
  table to be read.  Further access, using ldptr, causes other appropriate
  sections of the symbol table to be read (for example, if you call ldtbread,
  the symbols or externals are read).  To force sections for the symbol table
  in memory, call ldreadst with ST_P* constants ORed together from
  st_support.h.

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

  libmld.a.

RELATED INFORMATION
  fopen(3), ldclose(3), ldfcn(4).

Index for Section 3

Alphabetical listing for L

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