ar(0) — CLIX 3.1r7.6.28



  ar(0)                               CLIX                               ar(0)



  NAME

    ar - Common archive file format

  SYNOPSIS

    #include <ar.h>

  DESCRIPTION

    The ar archive command combines several files into one.  Archives are used
    mainly as libraries to be searched by the link editor ld.

    Each archive begins with the archive magic string.

    #define ARMAG  "<arch>\n" /* magic string */
    #define SARMAG 8           /* length of magic string */

    Each archive which contains common object files includes an archive symbol
    table.  This symbol table is used by the link editor ld to determine which
    archive members must be loaded during the link edit process.  The archive
    symbol table (if it exists) is always the first file in the archive (but
    is never listed) and is automatically created and/or updated by ar.

    Following the archive magic string are the archive file members.  Each
    file member is preceded by a file member header which is of the following
    format:

    #define ARFMAG "\n"   /* header trailer string */

    struct ar_hdr {        /* file member header */
         char ar_name[16]; /* '/' terminated file member name */
         char ar_date[12]; /* file member date */
         char ar_uid[6];   /* file member user identification */
         char ar_gid[6];   /* file member group identification */
         char ar_mode[8];  /* file member mode (octal) */
         char ar_size[10]; /* file member size */
         char ar_fmag[2];  /* header trailer string */
    };

    The ar_hdr contains the following members:

    ar_name   The blank-padded and slash (/) terminated filename.

    ar_date   The modification date of the file at the time of its insertion
              into the archive.

    ar_uid    The user ID of the owner of the file at the time of its
              insertion into the archive.

    ar_gid    The group ID of the owner of the file at the time of its



  2/94 - Intergraph Corporation                                              1



  ar(0)                               CLIX                               ar(0)



              insertion into the archive.

    ar_mode   The mode of the file.  This number is in octal.

    ar_size   The size of the file.  Reflects the size of the file excluding
              any padding.

    ar_fmag   The header trailer string.

    All information in the file member headers is in printable ASCII.  The
    numeric information contained in the headers is stored as decimal numbers
    (except for ar_mode which is in octal).  Thus, if the archive contains
    printable files, the archive itself is printable.

    Common format archives can be moved from system to system as long as the
    portable archive command ar is used.  Conversion tools such as convert
    exist to aid in the transportation of noncommon format archives to this
    format.

    Each archive file member begins on an even byte boundary; a newline is
    inserted between files if necessary.  Nevertheless the size given reflects
    the actual size of the file exclusive of padding.

    Notice there is no provision for empty areas in an archive file.

    If the archive symbol table exists, the first file in the archive has a
    zero length name (that is, ar_name[0] == '/').  The contents of this file
    are as follows:

    ⊕  The number of symbols.  Length: 4 bytes.

    ⊕  The array of offsets into the archive file.  Length: 4 bytes * ``the
       number of symbols''.

    ⊕  The name string table.  Length:  ar_size - (4 bytes * (the number of
       symbols + 1)).

    The number of symbols and the array of offsets are managed with sgetl()
    and sputl().  The string table contains exactly as many null terminated
    strings as there are elements in the offsets array.  Each offset from the
    array is associated with the corresponding name from the string table (in
    order).  The names in the string table are all the defined global symbols
    found in the common object files in the archive.  Each offset is the
    location of the archive header for the associated symbol.

  FILES

    /usr/include/ar.h

  CAUTIONS




  2                                              Intergraph Corporation - 2/94



  ar(0)                               CLIX                               ar(0)



    The strip command removes archive symbol entries from the header.  The
    archive symbol entries must be restored with the ts option of the ar
    command before the archive can be used with the link editor ld.

  RELATED INFORMATION

    Commands:  ar(1), ld(1), strip(1)

    Functions:  sputl(3)













































  2/94 - Intergraph Corporation                                              3

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