NAME

st_ar_member_next, st_file_is_archive, st_is_obj_archive, st_obj_close, st_obj_open, st_object_type − Routines to check whether an object is an archive and to process object files within an archive. 

LIBRARY

Symbol Table and Object File Access Library (libst.a)

SYNOPSIS

#include <st.h>

st_status_t st_obj_open (
        st_obj_t ∗∗obj,
        const char ∗file,
        unsigned int flags );

st_status_t st_obj_close (
        st_obj_t ∗obj );

st_status_t st_object_type (
        const char ∗file,
        st_object_type_t ∗otype );

st_status_t st_is_obj_archive (
        st_obj_t ∗obj,
        st_bool_t ∗is_archive);

st_status_t st_file_is_archive (
        char ∗file,
        st_bool_t ∗is_archive);

st_status_t st_ar_member_next (
        st_obj_t ∗obj);

PARAMETERS

objSpecifies an address to which st_obj_open returns an object handle if it successfully opens the file specified in the file parameter.  For st_obj_close, specifies an object handle, as returned by the st_obj_open function. 

fileSpecifies the file name of the object to be opened or closed, or for which an object type is requested. 

flagsSpecifies how the object is to be opened.  The open flags defined in /usr/include/st.h include the following:

ST_RDONLY
Opens the file for read-only access.  This is the default.

ST_MANGLE_NAMES
Disables name demangling for C++ names.  By default, C++ name demangling is enabled when a file is opened.

otypeSpecifies an address to which st_object_type returns a value identifying the object type.  The following object types are defined in usr/include/st.h:

ST_OTYPE_UNKNOWN
Unknown object type

ST_ARCHIVE
Archive library

ST_OMAGIC
OMAGIC file

ST_NMAGIC
NMAGIC file

ST_ZMAGIC
ZMAGIC file

is_archiveA boolean variable set to true if the file is an archive. 

DESCRIPTION

The st_obj_open function opens the named object file for read access.  It maps the file in memory using mmap, if possible.  If mmap fails, it dynamically allocates memory in which to read the file.  The flags parameter indicates how the file is to be opened.  If it succeeds in opening the file, it returns an opaque handle for the object to the obj parameter.  You can use this object handle as an input argument in subsequent calls to other object file access routines. 

The st_obj_close function releases memory dynamically allocated for processing the object and unmaps memory to which the file was mapped when it was opened. 

The st_object_type function returns the object type of the specified filename object to the otype parameter.  It does not create an object handle, nor does it open the object. 

If the named file is an archive file, st_obj_open initializes archive information in the obj structure and returns successfully. 

Archive member objects are processed sequentially.  After an archive has been successfully opened, call the st_ar_member_next routine.  It reads in an archive member each time it is called, and it returns ST_E_ARCHIVE_END when there are no more members.  If the archive contains no members, st_ar_member_next returns ST_E_ARCHIVE_EMPTY.  (See the code fragment in the Example section for proper usage of st_ar_member_next.) 

The routines st_is_obj_archive and st_file_is_archive can be used to detect whether a file or object handle is an archive.  Use st_file_is_archive before calling st_obj_open or st_obj_is_archive after calling st_obj_open. 

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 is if 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. 

EXAMPLE

The following code fragment illustrates how to use libst routines to open object files or archive libraries:

#include <st.h>
char ∗objname;
st_bool_t archive;
st_status_t status;
st_obj_t ∗obj;
...
if (argc != 2)
     return;
objname = argv[1];
if (status = st_obj_open(&obj, objname, ST_RDONLY))
     return status;
st_is_obj_archive(obj, &archive);
if (archive)
     while ((status = st_ar_member_next(obj)) == 0) {
             /∗ process member object ∗/
     }
else
     /∗ process object ∗/
st_obj_close(obj);
...

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: mmap(2), libst_intro(3), st_addr_to_file(3), st_file_lang(3), st_obj_calls(3), st_obj_file_start(3), st_objlist_append(3), st_proc_addr(3), st_sym_value(3)