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libst_intro(3)
NAME
  libst_intro, libst - Symbol table and object file access library

SYNOPSIS
  #include <st.h>

DESCRIPTION
  libst.a contains a collection of functions for accessing object file data
  and symbol table information.	 These functions effectively insulate the
  calling program from knowledge of the overall structure of the object file.
  An object can be a file with a .o suffix, a nonshared or call-shared
  executable, or a shared library.  The libst function can also be used to
  access objects in archive libraries.

  The libst.a functions are particularly useful for developing tools that
  must access file, procedure, symbol, or line number information.  They can
  assist in the development of Atom-based tools for application performance
  tuning and debugging.	 (See atom(1) for more information on the Atom tool
  kit.)

  The header file /usr/include/st.h contains all definitions and function
  prototypes needed for utilizing libst.a functions.  Some applications may
  also need to include the <cmplrs/demangle_string.h> header file to control
  name-demangling operations for C++ objects.  By default, name demangling is
  enabled by libst when an object is opened.

  Functions allow you to manage both a single object and lists of objects.
  Object lists are useful when a call-shared object and one or more shared
  libraries that it uses must be available simultaneously.

  Interface routines provide access to object file header information and the
  symbol table.	 The symbol table contains information on source files,
  procedures, symbols, symbol type/class/size information, and lines.
  Address look-up routines are provided for text, data, and bss addresses.
  Access is provided where applicable to obtain information at the list,
  object, and source file level. For example, you can obtain the number of
  procedures in an entire object, or the number of procedures in a particular
  file.	 Functions return handles for objects, files, procedures, and
  symbols.

  libst functions are reentrant but not threadsafe. The calling program must
  synchronize thread access to objects or lists of objects.  You should
  serialize access to an object list whenever an object is appended or when
  the object list is closed.  At the object level, you should serialize calls
  to st_proc_sort, for instance. If a thread changes name demangling for an
  object, then you should both set the name-demangling flag and perform the
  name translation before another thread makes a name-translation call, such
  as st_sym_name.  Generally, most calls to libst are read requests and do
  not require synchronization.

EXAMPLES
  The following code example shows how to use libst routines to list the file
  and procedure names in an object file.


  The build command for this program is:

  cc -g test.c -o test -lst -lmld

  This command ensures that libst will use any newer C++ demangler that has
  been installed along with a C++ compiler. The program is linked as a call-
  shared program, so the demangler in libmld.a loads libdemangle.so
  dynamically using ldopen(3), and it runs the shared library's demangler if
  that one is newer. To link a non-shared program so that libst uses a newer
  (or older) demangler in libdemangle.a, use this build command:

  cc -non_shared test.c -o test -lst -all -qldemangle -none -lmld

	 #include <st.h>

	 main(int argc, char **argv)
	 {
	    st_status_t ret;
	    st_obj_t *obj;
	    st_file_t file;
	    st_proc_t proc;
	    unsigned int fcount;
	    unsigned int pcount;
	    char *fname;
	    char *pname;
	    st_bool_t stripped;
	    st_addr_t paddr;
	    int i, j;

	    if(argc < 2) {
	       printf("Usage: test object_name\n");
	       exit(1);
	    }

	    /* Open the object.	 For C++, name demangling is enabled
	     * when an object is successfully opened.
	     */
	    if((ret = st_obj_open(&obj, argv[1], ST_RDONLY))) {
	       printf("open ret = %d\n",ret);
	       exit(1);
	    }

	    /* If the object is stripped, exit since no symbolic
	     * information is available.
	     */
	    st_is_obj_stripped(obj, &stripped);
	    if(stripped) {
	       printf("Object %s is stripped\n", argv[1]);
	       exit(0);
	    }
	    /* Get handle for first file in the object and the count
	     * of files.
	     */
	    st_obj_file_start(obj, &file);
	    st_obj_file_count(obj, &fcount);

	    /* Loop through the files in the object, printing the
	     * procedures contained in each.  File names and static
	     * procedure names are unavailable for files that were not
	     * compiled with -g.
	     */
	    for(i = 0; i < fcount; i++) {
	       st_is_file_locally_stripped(obj, file, &stripped);
	       if(stripped)
		  printf("File is locally stripped - name is unavailable:\n");
	       else {
		  st_file_name(obj, file, &fname);
		  printf("File %s:\n", fname);
	       }
	       /* Get handle for first procedure for this file, and the
		* count of procedures in the file.
		*/
	       st_file_proc_start(obj, file, &proc);
	       st_file_proc_count(obj, file, &pcount);

	       /* Loop through the procedures for the file, printing the
		* procedure name if available.	Static procedure names are not
		* available, for example, if the file was not compiled with -g.
		*/
	       for(j=0; j < pcount; j++) {
		  st_file_t fi;
		  char *fn;

		  /* If name lookup fails, get the procedure address */
		  if((ret = st_proc_name(obj, proc, &pname)))
		     st_proc_addr(obj, proc, &paddr);
		  if(!ret)
		     printf("	Procedure %s\n", pname);
		  else
		     printf("	Procedure at 0x%p\n",paddr);
		  st_file_proc_next(obj, file, proc, &proc);
	       }
	       st_obj_file_next(obj, file, &file);
	    }
	    ret = st_obj_close(obj);
	    if (ret) {
	       printf("close ret = %d\n",ret);
	       exit(1);
	    }
	    exit (0);
	 }

RETURN VALUES
  All functions indicate success by returning a value of 0 (zero).  A
  positive return value is an errno value from a system call.  A negative
  return value is a library error or informational code.  The library codes
  are documented in st.h.

  Return parameters are set to 0 or -1 when an error occurs.  Address
  parameters are set to 0, and file and procedure handles are set to -1.  An
  exception to this occurs when a NULL pointer for the object or other return
  parameter is input.  In these cases, the return parameters will be
  unchanged.  A non-zero return status is the recommended method for
  detecting an error return from a libst function.

FILES
  /usr/include/st.h
	    Header file that contains all definitions and function prototypes
	    for libst.a functions

  /usr/include/cmplrs/demangle_string.h
	    Header file that controls name-demangling operations for C++
	    objects

RELATED INFORMATION
  Commands: atom(1)

  Functions: st_addr_to_file(3), st_cm_setup(3), st_file_lang(3),
  st_get_known_versions(3), st_lang_str(3), st_obj_calls(3),
  st_obj_file_start(3), st_obj_open(3), st_objlist_append(3),
  st_proc_addr(3), st_strerror(3), st_sym_value(3).

Index for Section 3

Alphabetical listing for L

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