Index for Section 4

Alphabetical listing for A

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ar(4)
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, followed 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 contains 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 insertion
  into the archive.

  Each file begins on an 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 padding.

  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.

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

RELATED INFORMATION
  ar(1), ld(1), nm(1)

Index for Section 4

Alphabetical listing for A

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