IEEE P1003.2b Draft 2 - December 1991 Copyright (c) 1991 by the Institute of Electrical and Electronics Engineers, Inc. 345 East 47th Street New York, NY 10017, USA All rights reserved as an unpublished work. This is an unapproved and unpublished IEEE Standards Draft, subject to change. The publication, distribution, or copying of this draft, as well as all derivative works based on this draft, is expressly prohibited except as set forth below. Permission is hereby granted for IEEE Standards Committee participants to reproduce this document for purposes of IEEE standardization activities only, and subject to the restrictions contained herein. Permission is hereby also granted for member bodies and technical committees of ISO and IEC to reproduce this document for purposes of developing a national position, subject to the restrictions contained herein. 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Box 1331 Piscataway, NJ 08855-1331, USA +1 (908) 562-3800 +1 (908) 562-1571 [FAX] P1003.2b Draft 3 STANDARDS PROJECT Draft Standard for Information Technology -- Portable Operating System Interface (POSIX) Part 2: Shell and Utilities -- Amendment 2 Sponsor Technical Committee on Operating Systems and Application Environments of the IEEE Computer Society Work Item Number: JTC 1.22.21.2 Abstract: P1003.2b is part of the POSIX series of standards for applications and user interfaces to open systems. It consists of modifications and clarifications to ISO/IEC 9945-2: 199x (IEEE Std 1003.2-199x and IEEE Std 1003.2a-199x), including support for symbolic links and a new archive/interchange format. Keywords: API, application portability, data processing, open systems, operating system, portable application, POSIX, shell and utilities, user portability P1003.2b / D3 February 1992 Copyright (c) 1991 by the Institute of Electrical and Electronics Engineers, Inc. 345 East 47th Street New York, NY 10017, USA All rights reserved. _T_h_i_s _i_s _a_n _u_n_a_p_p_r_o_v_e_d _I_E_E_E _S_t_a_n_d_a_r_d_s _D_r_a_f_t, _s_u_b_j_e_c_t _t_o _c_h_a_n_g_e. _P_e_r_m_i_s_s_i_o_n _i_s _h_e_r_e_b_y _g_r_a_n_t_e_d _f_o_r _I_E_E_E _S_t_a_n_d_a_r_d_s _C_o_m_m_i_t_t_e_e _p_a_r_t_i_c_i_p_a_n_t_s _t_o _r_e_p_r_o_d_u_c_e _t_h_i_s _d_o_c_u_m_e_n_t _f_o_r _p_u_r_p_o_s_e_s _o_f _I_E_E_E _s_t_a_n_d_a_r_d_i_z_a_t_i_o_n _a_c_t_i_v_i_t_i_e_s. _P_e_r_m_i_s_s_i_o_n _i_s _a_l_s_o _g_r_a_n_t_e_d _f_o_r _m_e_m_b_e_r _b_o_d_i_e_s _a_n_d _t_e_c_h_n_i_c_a_l _c_o_m_m_i_t_t_e_e_s _o_f _I_S_O _a_n_d _I_E_C _t_o _r_e_p_r_o_d_u_c_e _t_h_i_s _d_o_c_u_m_e_n_t _f_o_r _p_u_r_p_o_s_e_s _o_f _d_e_v_e_l_o_p_i_n_g _a _n_a_t_i_o_n_a_l _p_o_s_i_t_i_o_n. _O_t_h_e_r _e_n_t_i_t_i_e_s _s_e_e_k_i_n_g _p_e_r_m_i_s_s_i_o_n _t_o _r_e_p_r_o_d_u_c_e _t_h_i_s _d_o_c_u_m_e_n_t _f_o_r _s_t_a_n_d_a_r_d_i_z_a_t_i_o_n _o_r _o_t_h_e_r _a_c_t_i_v_i_t_i_e_s, _o_r _t_o _r_e_p_r_o_d_u_c_e _p_o_r_t_i_o_n_s _o_f _t_h_i_s _d_o_c_u_m_e_n_t _f_o_r _t_h_e_s_e _o_r _o_t_h_e_r _u_s_e_s, _m_u_s_t _c_o_n_t_a_c_t _t_h_e _I_E_E_E _S_t_a_n_d_a_r_d_s _D_e_p_a_r_t_m_e_n_t _f_o_r _t_h_e _a_p_p_r_o_p_r_i_a_t_e _l_i_c_e_n_s_e. _U_s_e _o_f _i_n_f_o_r_m_a_t_i_o_n _c_o_n_t_a_i_n_e_d _i_n _t_h_i_s _u_n_a_p_p_r_o_v_e_d _d_r_a_f_t _i_s _a_t _y_o_u_r _o_w_n _r_i_s_k. IEEE Standards Department Copyright and Permissions 445 Hoes Lane, P.O. Box 1331 Piscataway, NJ 08855-1331, USA +1 (908) 562-3800 +1 (908) 562-1571 [FAX] _F_e_b_r_u_a_r_y _1_9_9_2 _S_H _X_X_X_X_X BEGIN_RATIONALE _E_d_i_t_o_r'_s _N_o_t_e_s This section will not appear in the final document. It is used for editorial comments concerning this draft. Draft 1 was mostly the new archive/interchange format, based on Donn Terry's work in P1003.1b. See the Introduction for other input the working group needs to consider. 2 This first draft contained diff marks (1) to differentiate material from 2 Donn's archive proposal; see 4.48. Diff marks ``2'' denote changes from 3 Draft 1 to Draft 2. Diff marks ``3'' denote changes from Draft 2 to 3 Draft 1. Editorial changes such as typos, grammatical errors or changes, changes in cross references, and removal of editorial notes are not diff-marked. Please note that it is not always feasible to get the diff marks exactly right; they will sometimes start or end a line too soon. This draft makes assumptions about the organization and content of POSIX.2 Draft 11.2, POSIX.2a Draft 8, and POSIX.1a Draft 5. If you are 3 not in one of these balloting groups, you can purchase either draft by 3 contacting: IEEE Publications P.O. Box 1331 445 Hoes Lane Piscataway, NJ 08855-1331 1 (800) 678-IEEE +1 (908) 562-3800 (outside US) Since portions of this standard are meant to be modifications of the base POSIX.2 standard, the draft headings in Sections 1 through 6 have been set up to match the affected clauses and still go into the table of contents. There are therefore gaps in the clause numbers. For various editorial reasons, there is a page number gap where the Annexes will eventually go. Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. _P_l_e_a_s_e _r_e_p_o_r_t _t_y_p_o_g_r_a_p_h_i_c_a_l _e_r_r_o_r_s _t_o: Hal Jespersen POSIX Software Group 447 Lakeview Way Redwood City, CA 94062 +1 (415) 364-3410 FAX: +1 (415) 364-4498 Email: hlj@Posix.COM (_E_l_e_c_t_r_o_n_i_c _m_a_i_l _i_s _p_r_e_f_e_r_r_e_d.) Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. This draft is available in various electronic forms to assist the review process. Our thanks to Andrew Hume of AT&T Bell Laboratories for providing online access facilities. Note that this is a limited experiment in providing online access; future ballots may provide other forms, such as diskettes or a bulletin board arrangement, but the instructions shown here are the only methods currently available. Please also observe the additional copyright restrictions that are described in the online files. Assuming you have access to the Internet, the scenario is approximately ftp research.att.com # research's IP address is 192.20.225.2 cd posix/p1003.2b/d3 get toc index binary get p11-20.Z The draft is available in several forms. The table of contents can be found in toc, pages containing a particular section are stored under the section number, sets of pages are stored in files with names of the form p_n-_m, and the entire draft is stored in all. By default, files are ASCII. A .ps suffix indicates PostScript. A .Z suffix indicates a compress'_e_d file. The file index contains a general description of the files available. These files are also available via electronic mail by sending a message like echo send 4.48 from posix/p1003.2b/d3 | mail netlib@research.att.com If you use email, you should _n_o_t ask for the compressed version. For a more complete introduction to this form of _n_e_t_l_i_b, send the message send help _P_O_S_I_X._2_b _C_h_a_n_g_e _H_i_s_t_o_r_y This section is provided to track major changes between drafts. Draft 3 [February 1992] Miscellaneous minor changes to the pax 3 format, provided by Mark Brown. Symbolic link material 3 added, based on initial proposals from Dawn Burnett, as 3 modified by the working group. 3 Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. Draft 2 [December 1991] Miscellaneous minor changes to the pax 2 format, provided by Mark Brown. Limited online access 2 provided as part of an IEEE Computer Society experiment. 2 Draft 1 [September 1991] Conversion of pax formatting from P1003.1b Draft 5 and cpio and pax from IEEE Std 1003.1- 1990. END_RATIONALE Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. IEEE Standards documents are developed within the Technical Committees of the IEEE Societies and the Standards Coordinating Committees of the IEEE Standards Board. Members of the committees serve voluntarily and without compensation. They are not necessarily members of the Institute. The standards developed within IEEE represent a consensus of the broad expertise on the subject within the Institute as well as those activities outside of IEEE that have expressed an interest in participating in the development of the standard. Use of an IEEE Standard is wholly voluntary. The existence of an IEEE Standard does not imply that there are no other ways to produce, test, measure, purchase, market, or provide other goods and services related to the scope of the IEEE Standard. Furthermore, the viewpoint expressed at the time a standard is approved and issued is subject to change brought about through developments in the state of the art and comments received from users of the standard. Every IEEE Standard is subjected to review at least every five years for revision or reaffirmation. When a document is more than five years old and has not been reaffirmed, it is reasonable to conclude that its contents, although still of some value, do not wholly reflect the present state of the art. Users are cautioned to check to determine that they have the latest edition of any IEEE Standard. Comments for revision of IEEE Standards are welcome from any interested party, regardless of membership affiliation with IEEE. Suggestions for changes in documents should be in the form of a proposed change of text, together with appropriate supporting comments. Interpretations: Occasionally questions may arise regarding the meaning of portions of standards as they relate to specific applications. When the need for interpretations is brought to the attention of the IEEE, the Institute will initiate action to prepare appropriate responses. Since IEEE Standards represent a consensus of all concerned interests, it is important to ensure that any interpretation has also received the concurrence of a balance of interests. For this reason, the IEEE and the members of its technical committees are not able to provide an instant response to interpretation requests except in those cases where the matter has previously received formal consideration. Comments on standards and requests for interpretations should be addressed to: Secretary, IEEE Standards Board 445 Hoes Lane P.O. Box 1331 Piscataway, NJ 08855-1331 Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. ___________________________________________________________ | IEEE Standards documents are adopted by the Institute of | | Electrical and Electronics Engineers without regard to | | whether their adoption may involve patents on articles, | | materials, or processes. Such adoption does not assume | | any liability to any patent owner, nor does it assume any| | obligation whatever to parties adopting the standards | | documents. | |___________________________________________________________| Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. Contents PAGE Introduction......................................................... iv Section 1: Revisions to General...................................... 1 1.1 Scope....................................................... 1 1.2 Normative References........................................ 1 1.3 Conformance................................................. 2 1.4 Test Methods................................................ 2 Section 2: Revisions to Terminology and General Requirements......... 3 2.2.2 General Terms....................................... 3 2.9.2 Pathname Resolution................................. 3 2.11.3 Operands............................................ 4 2.13.3 Pathname Variable Values............................ 5 Section 3: Revisions to Shell Command Language....................... 7 Section 4: Revisions to Execution Environment Utilities.............. 9 4.5 cd - Change working directory............................... 9 4.6 chgrp - Change file group ownership......................... 10 4.7 chmod - Change file modes................................... 11 4.8 chown - Change file ownership............................... 12 4.13 cp - Copy files............................................. 13 4.24 find - Find files........................................... 14 4.33 ln - Link files............................................. 15 4.39 ls - List directory contents................................ 17 4.43 mv - Move files............................................. 18 4.48 pax - Portable archive interchange.......................... 19 4.51 pwd - Return working directory name......................... 67 4.53 rm - Remove directory entries............................... 68 4.62 test - Evaluate expression.................................. 69 Section 5: Revisions to User Portability Utilities Option............ 71 5.9 du - Estimate file usage.................................... 71 5.39 file - Determine file type.................................. 72 Section 6: Revisions to Software Development Utilities Option........ 73 Annex A (normative) Revisions to C Language Development Utilities Option............................................................ 75 Annex B (normative) Revisions to C Language Bindings Option.......... 77 B.2.5 Pathname Variable Values............................ 77 Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. ii PAGE Alphabetic Topical Index............................................. 79 TABLES Table 2-100 - Pathname Variable Values............................. 6 Table 4-100 - Octet-Oriented cpio Archive Entry.................... 56 Table 4-101 - tar Header Block..................................... 62 Table B-100 - C Pathname Variable Values........................... 77 Table B-101 - C Bindings for Pathname Configurable Variables....... 78 Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. iii Introduction (This Introduction is not a normative part of P1003.2b Information technology -- Portable Operating System Interface (POSIX) -- Part 2: Shell and Utilities -- Amendment 2, but is included for information only.) _H_L_J: _T_o _b_e _p_r_o_v_i_d_e_d. _B_r_i_e_f_l_y, _P_O_S_I_X._2_b _c_o_n_s_i_s_t_s _o_f _m_i_n_o_r _c_h_a_n_g_e_s _t_o _a_c_c_o_m_p_l_i_s_h _t_h_e _f_o_l_l_o_w_i_n_g (_f_r_o_m _P_A_R): (_1) _R_e_s_o_l_v_e _i_n_t_e_r_n_a_t_i_o_n_a_l _c_o_m_m_e_n_t_s _o_n _I_S_O/_I_E_C _D_I_S _9_9_4_5-_2 _a_n_d _9_9_4_5- _2/_D_A_M _1 (_P_1_0_0_3._2 _a_n_d _P_1_0_0_3._2_a). (_2) _R_e_s_o_l_v_e _i_s_s_u_e_s _r_e_s_u_l_t_i_n_g _f_r_o_m _r_e_q_u_e_s_t_s _f_o_r _i_n_t_e_r_p_r_e_t_a_t_i_o_n _o_f _t_h_e _o_r_i_g_i_n_a_l _I_E_E_E _1_0_0_3._2 _a_n_d _1_0_0_3._2_a _d_o_c_u_m_e_n_t_s. (_3) _I_m_p_r_o_v_e _t_h_e _c_l_a_r_i_t_y, _a_c_c_u_r_a_c_y, _a_n_d _p_r_e_c_i_s_i_o_n _o_f _t_h_e _l_a_n_g_u_a_g_e _i_n _t_h_e _o_r_i_g_i_n_a_l _1_0_0_3._2 _a_n_d _1_0_0_3._2_a _d_o_c_u_m_e_n_t_s, _c_o_r_r_e_c_t_i_n_g _d_e_f_i_c_i_e_n_c_i_e_s _f_o_u_n_d _i_n _i_m_p_l_e_m_e_n_t_i_n_g _s_y_s_t_e_m_s, _t_e_s_t _s_u_i_t_e_s, _o_r _a_p_p_l_i_c_a_t_i_o_n_s _b_a_s_e_d _o_n _t_h_e _d_o_c_u_m_e_n_t_s. (_4) _R_e_s_o_l_v_e _i_s_s_u_e_s _i_d_e_n_t_i_f_i_e_d _b_y _I_E_E_E _w_o_r_k_i_n_g _g_r_o_u_p_s _p_r_o_d_u_c_i_n_g _f_u_n_c_t_i_o_n_a_l _s_t_a_n_d_a_r_d_s (_p_r_o_f_i_l_e_s) _t_h_a_t _d_e_s_i_r_e _f_i_n_e_r _g_r_a_n_u_l_a_r_i_t_y _i_n _g_r_o_u_p_i_n_g_s _o_f _o_p_t_i_o_n_a_l _u_t_i_l_i_t_i_e_s _a_n_d _f_e_a_t_u_r_e_s. (_5) _I_n_c_o_r_p_o_r_a_t_e _i_n_t_e_r_f_a_c_e_s _a_s_s_o_c_i_a_t_e_d _w_i_t_h _n_e_w _f_a_c_i_l_i_t_i_e_s _b_e_i_n_g _p_r_o_d_u_c_e_d _b_y _t_h_e _P_1_0_0_3._1_a _p_r_o_j_e_c_t, _s_u_c_h _a_s _s_y_m_b_o_l_i_c _l_i_n_k_s. (_N_o_t_e: _E_x_t_e_n_d_e_d _o_r _s_u_p_p_l_e_m_e_n_t_a_r_y _s_h_e_l_l _a_n_d _u_t_i_l_i_t_y _f_e_a_t_u_r_e_s _b_a_s_e_d _o_n _P_1_0_0_3._1_a _i_n_t_e_r_f_a_c_e_s _w_i_l_l _b_e _i_n_c_l_u_d_e_d _i_n _P_1_0_0_3._2_b _o_n_l_y _i_f _s_c_h_e_d_u_l_e_s _c_a_n _b_e _a_r_r_a_n_g_e_d _s_o _t_h_a_t _t_h_e _P_1_0_0_3._1_a _s_u_p_p_l_e_m_e_n_t _i_s _a_v_a_i_l_a_b_l_e _f_o_r _c_i_t_a_t_i_o_n _a_s _a _n_o_r_m_a_t_i_v_e _r_e_f_e_r_e_n_c_e _a_t _t_h_e _t_i_m_e _o_f _a_p_p_r_o_v_a_l _o_f _P_1_0_0_3._2_b.) (_6) _A_s_s_u_m_e _r_e_s_p_o_n_s_i_b_i_l_i_t_y _f_o_r _d_e_f_i_n_i_t_i_o_n _o_f _f_i_l_e _i_n_t_e_r_c_h_a_n_g_e _a_n_d _a_r_c_h_i_v_i_n_g _f_o_r_m_a_t_s _f_r_o_m _P_1_0_0_3._1. _T_h_i_s _w_o_u_l_d _i_n_v_o_l_v_e _m_o_v_e_m_e_n_t _o_f _t_h_e _c_u_r_r_e_n_t _s_e_c_t_i_o_n _1_0 _i_n _I_E_E_E _S_t_d _1_0_0_3._1-_1_9_9_0 _a_n_d _t_h_e _p_r_o_p_o_s_e_d _n_e_w _f_o_r_m_a_t _f_r_o_m _P_1_0_0_3._1_a _t_o _t_h_e _c_l_a_u_s_e _i_n _P_1_0_0_3._2 _t_h_a_t _d_e_s_c_r_i_b_e_s _t_h_e ``_p_a_x'' _u_t_i_l_i_t_y. Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. iv Introduction _R_e_l_a_t_e_d__S_t_a_n_d_a_r_d_s__A_c_t_i_v_i_t_i_e_s Activities to extend this standard to address additional requirements are in progress, and similar efforts can be anticipated in the future. The following areas are under active consideration at this time, or are expected to become active in the near future:1) (1) Language-independent service descriptions of POSIX.1 {8} (2) C, Ada, and Fortran Language bindings to (1) (3) Verification testing methods (4) Realtime facilities (5) Secure/Trusted System considerations (6) Network interface facilities (7) System Administration (8) Graphical User Interfaces (9) Profiles describing application- or user-specific combinations of Open Systems standards for: supercomputing, multiprocessor, and batch extensions; transaction processing; realtime systems; and multiuser systems based on historical models (10) An overall guide to POSIX-based or related Open Systems standards and profiles Extensions are approved as ``amendments'' or ``revisions'' to this document, following the IEEE and ISO/IEC Procedures. Approved amendments are published separately until the full document is reprinted and such amendments are incorporated in their proper positions. __________ 1) A _S_t_a_n_d_a_r_d_s _S_t_a_t_u_s _R_e_p_o_r_t that lists all current IEEE Computer Society standards projects is available from the IEEE Computer Society, 1730 Massachusetts Avenue NW, Washington, DC 20036-1903; Telephone: +1 202 371-0101; FAX: +1 202 728-9614. Working drafts of POSIX standards under development are also available from this office. Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. Introduction v If you have interest in participating in the TCOS working groups addressing these issues, please send your name, address, and phone number to the Secretary, IEEE Standards Board, Institute of Electrical and Electronics Engineers, Inc., P.O. Box 1331, 445 Hoes Lane, Piscataway, NJ 08855-1331, and ask to have this forwarded to the chairperson of the appropriate TCOS working group. If you have interest in participating in this work at the international level, contact your ISO/IEC national body. P1003.2b was prepared by the 1003.2b working group, sponsored by the Technical Committee on Operating Systems and Application Environments of the IEEE Computer Society. At the time this standard was approved, the membership of the 1003.2b working group was as follows: Technical Committee on Operating Systems and Application Environments (TCOS) Chair: Jehan-Francois Pa^ris TCOS Standards Subcommittee Chair: Jim Isaak Vice Chairs: Ralph Barker Robert Bismuth Hal Jespersen Lorraine Kevra Pete Meier Treasurer: Quin Hahn Secretary: Shane McCarron 1003.2b Working Group Officials Chair: Hal Jespersen Vice Chair: Donald W. Cragun Editor: Hal Jespersen Secretary: Dave Grindeland Technical Reviewers John Q. Public John Q. Public Jane Doe Jane Doe John Q. Public John Q. Public Working Group Jane Doe John Q. Public John Q. Public John Q. Public Jane Doe John Q. Public Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. vi Introduction The following persons provided valuable input during the balloting period: John Q. Public Jane Doe John Q. Public Jane Doe John Q. Public John Q. Public The following persons were members of the 1003.2b balloting group that approved the standard for submission to the IEEE Standards Board: John Q. Public _T_B_D _I_n_s_t_i_t_u_t_i_o_n_a_l _R_e_p_r_e_s_e_n_t_a_t_i_v_e Jane Doe John Q. Public John Q. Public John Q. Public John Q. Public Jane Doe When the IEEE Standards Board approved this standard on <_d_a_t_e _t_o _b_e _p_r_o_v_i_d_e_d>, it had the following membership: (to be pasted in by IEEE) END_RATIONALE Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. Introduction vii P1003.2b/D3 Information technology -- Portable Operating System Interface (POSIX) -- Part 2: Shell and Utilities -- Amendment 2 Section 1: Revisions to General 1.1 Scope _H_L_J: _T_o _b_e _p_r_o_v_i_d_e_d. _S_e_e _t_h_e _I_n_t_r_o_d_u_c_t_i_o_n. _P_r_o_p_o_s_e_d _t_e_x_t _i_s _s_o_l_i_c_i_t_e_d. 1.2 Normative References => 1.2 Normative References. _A_d_d _t_h_e _f_o_l_l_o_w_i_n_g _e_n_t_r_i_e_s _t_o _t_h_e _N_o_r_m_a_t_i_v_e _R_e_f_e_r_e_n_c_e_s _c_l_a_u_s_e _i_n _t_h_e _c_o_r_r_e_c_t _s_o_r_t_e_d _s_e_q_u_e_n_c_e, _d_i_s_r_e_g_a_r_d_i_n_g _t_h_e _s_e_q_u_e_n_c_e _n_u_m_b_e_r_s _s_h_o_w_n _h_e_r_e. {9} ISO 1001: 1986, _I_n_f_o_r_m_a_t_i_o_n _p_r_o_c_e_s_s_i_n_g--_F_i_l_e _s_t_r_u_c_t_u_r_e _a_n_d _l_a_b_e_l_l_i_n_g _o_f _m_a_g_n_e_t_i_c _t_a_p_e_s _f_o_r _i_n_f_o_r_m_a_t_i_o_n _i_n_t_e_r_c_h_a_n_g_e. Issue: _T_h_e _f_o_l_l_o_w_i_n_g _t_h_r_e_e _s_t_a_n_d_a_r_d_s _s_e_e_m _t_o _c_o_r_r_e_s_p_o_n_d _t_o _A_N_S_I _X_3._1_4, _2_2, _3_9, _a_n_d _5_4. _S_o_m_e_o_n_e _w_i_t_h _a_c_c_e_s_s _t_o _t_h_e _a_c_t_u_a_l _d_o_c_u_m_e_n_t_s _s_h_o_u_l_d _c_h_e_c_k _t_h_i_s _a_s_s_u_m_p_t_i_o_n _c_a_r_e_f_u_l_l_y. {10} ISO 1863: 1976, _I_n_f_o_r_m_a_t_i_o_n _p_r_o_c_e_s_s_i_n_g--_9-_t_r_a_c_k, _1_2,_7 _m_m (_0._5 _i_n) _w_i_d_e _m_a_g_n_e_t_i_c _t_a_p_e _f_o_r _i_n_f_o_r_m_a_t_i_o_n _i_n_t_e_r_c_h_a_n_g_e _r_e_c_o_r_d_e_d _a_t _3_2 _r_p_m_m (_8_0_0 _r_p_i). Copyright (c) 1992 IEEE. All rights reserved. This is an unapproved IEEE Standards Draft, subject to change. 1.2 Normative References 1