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

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

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

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

  ldreadst(
	  LDFILE *ldptr,
	  int flags );

LIBRARY
  libmld.a

DESCRIPTION
  The ldopen() and ldclose() 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.

  The ldopen() and ldclose() 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, and
  particularly when a new filename is opened, ldopen() should be called with
  a 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 again 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() and ldaopen() functions 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, by 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.

SEE ALSO
  fopen(3), ldclose(3), ldfcn(4)

Index for Section 3

Alphabetical listing for L

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