<para>A few typos in the original have been fixed; if you're really
curious, comments in the XML source describe them. Variant spellings
-such as <quote>imbedded</wquote> have vbeen preserved.</para>
+such as <quote>imbedded</quote> have been preserved.</para>
<para>The original was not continuously page-numbered. Instead the
pages were numbered within each chapter with the chapter number as
encountered. If the statement EXECUTED SETEOF. (0) is executed the
read routines will be reset to enter SYSTEM. when an end-of-file is
encountered.</para>
+
+<para>Normally, if an end-of-tape is encountered while executing a
+WRITE BCD TAPE or WRITE BINARY TAPE statement, the tape is rewound, a
+comment indicating this is printed for the operator, and the computer
+is halted so that the operator can replace the tape. The program is
+then continued from where the end-of-tape was detected. Thus, no
+information is lost and the new tape is a continuation of the old one.
+This action can be changed by executing the statement EXECUTE
+SETETT. (&scriptS;). The subroutine SETETT. sets the write tape
+routines to transfer to the executable statement labelled &scriptS;
+when an end-of-tape is encountered. The tape is not rewound nor is
+any comment printed for the operator and the computer does not stop
+before this transfer occurs. Executing EXECUTE SETETT.(0) will reset
+the write tape routines to the normal action.</para>
+
+<para>The subroutines SETEOF. and SETETT. may be executed as many
+times as desired. Only one setting is in effect for end-of-file (that
+specified by the latest execution of SETOFF.) and end-of-tape (that
+specified by the latest execution of SETETT.), i.e., each setting
+cancels the previous one.</para>
+</sect3>
+</sect2>
+<sect2><title>FORMAT SPECIFICATIONS</title>
+
+<para>When information is read from (or punched in) a card into (or from) a
+computer, it is necessary to know how this information has been
+allocated among the available columns of the card. Similarly,
+whenever information is to be printed by a printer (either on-line of
+off-line), it is necessary to know how this information has been
+allocated among the columns available on the printer. A description
+of each allocation is called a format specification. Usually, but not
+always, such a specification is accompanied by a list of variables
+whose values are to be printed or punched or whose values are to be
+read. (Occasionally, the information is contined entirely in the
+format specification, so the list may be empty.) A format
+specification is a string of alphabetic characters (as described
+below) terminated by an "*". This string is stored six characters per
+computer word in a vector with integer mode. This vector may be
+preset (see section 3.7), computed, or read in as data.</para>
+
+<sect3><title>Carriage Control</title>
+
+<para>Every format specification consists of a description of the allocation
+of available columns, and the form in which the particular information
+is to appear. Specifications for reading or punching cards and
+printing of information are identical, whith the following exceptions:</para>
+
+<para>(a) A card has only 72 available
+columns<footnote><para>Actually, 80 columns may be usd, provided the
+proper computer hardware configuration is available. The use of 72
+columns is always safe, however, and strongly
+recommended. </para></footnote> while a line of print has 120
+available columns. Any attempt to allocate more than the available
+number of columns will cause an error return (see section
+2.14.1).</para>
+
+<para>(b) The first columnof a card has no special significance. The first
+(left-most) character of a line of print is treated differently. This
+character governs printer carriage control, much as skipping to a new
+page, double spacing, etc. and should not contin information to be
+printed. The user has effectively 119 available columns on a line of
+print, but he must always include the first character as a code to
+control the vertical spacing for that line.</para>
+
+<para>For example, the specification</para>
+
+<programlisting>
+S16, 6HBETA =I2*
+</programlisting>
+
+<para>will indicate that the line (or card) starts with a skip of 16 columns
+and then prints (or reads or punches) the characters "BETA =" followed
+by an integer field of two columns. If a card is involved, the letter
+"B" in "BETA" will be found in column 17, due to the skip of 16
+columns. However, if a line is to be printed, the "B" will print in
+column 16 of the printed page, since the first character of the line
+(in this case, the first of the 16 columns to be skipped) is detached,
+to be interpreted as carriage control leaving an effective skip of 15
+columns. The effect of a "blank" character on carriage control is to
+move to the next line before printing, as will be seen from the
+following table. In each case the carriage control character is
+effective before the rest of the specification is carried out.</para>
</sect3>
</sect2>
</sect1>
projects / mad.git / commitdiff