AR(4-SysV)          RISC/os Reference Manual           AR(4-SysV)



NAME
     ar - archive (library) file format

SYNOPSIS
     #include <ar.h>

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

     A file produced by ar has a magic string at the start, fol-
     lowed by the constituent files, each preceded by a file
     header.  The magic number and header layout as described in
     the include file are:

                        COMMON ARCHIVE FORMAT

                 ARCHIVE File Organization:
                 _______________________________________________
                 |__________ARCHIVE_MAGIC_STRING_______________|
                 |__________ARCHIVE_FILE_MEMBER_1______________|
                 |                                             |
                 |       Archive File Header "ar_hdr"           |
                 |.............................................|
                 |       Member Contents                       |
                 |              1. External symbol directory   |
                 |              2. Text file                   |
                 |_____________________________________________|
                 |________ARCHIVE_FILE_MEMBER_2________________|
                 |              "ar_hdr"                        |
                 |.............................................|
                 |       Member Contents (.o or text file)     |
                 |_____________________________________________|
                 |       .              .              .       |
                 |       .              .              .       |
                 |       .              .              .       |
                 |_____________________________________________|
                 |________ARCHIVE_FILE_MEMBER_n________________|
                 |              "ar_hdr"                        |
                 |.............................................|
                 |              Member Contents                |
                 |_____________________________________________|



     The name is a blank-padded string.  The ar_fmag field con-
     tains ARFMAG to help verify the presence of a header.  The
     other fields are left-adjusted, blank-padded numbers.  They
     are decimal except for ar_mode, which is octal.  The date is
     the modification date of the file at the time of its inser-
     tion into the archive.



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AR(4-SysV)          RISC/os Reference Manual           AR(4-SysV)



     Each file begins on a even (0 mod 2) boundary; a new-line is
     inserted between files if necessary.  Nevertheless the size
     given reflects the actual size of the file exclusive of pad-
     ding.

     There is no provision for empty areas in an archive file.

     The encoding of the header is portable across machines.  If
     an archive contains printable files, the archive itself is
     printable.

SEE ALSO
     ar(1), ld(1), nm(1) in the User's Reference Manual.

BUGS
     File names lose trailing blanks.  Most software dealing with
     archives takes even an included blank as a name terminator.






































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