VC(1SCCS)               COMMAND REFERENCE               VC(1SCCS)



NAME
     vc - version control

SYNOPSIS
     vc [ -a ][ -t ][ -cchar ][ -s ][
     keyword=value....keyword=value ]

DESCRIPTION
     The vc command copies lines from the standard input to the
     standard output under control of its arguments and control
     statements encountered in the standard input.  In the
     process of performing the copy operation, user declared
     keywords may be replaced by their string value when they
     appear in plain text and/or control statements.

     The copying of lines from the standard input to the standard
     output is conditional, based on tests (in control
     statements) of keyword values specified in control
     statements or as vc command arguments.

     A control statement is a single line beginning with a
     control character, except as modified by the -t keyletter
     (see below).  The default control character is colon (:),
     except as modified by the -c keyletter (see below).  Input
     lines beginning with a backslash (\) followed by a control
     character are not control lines and are copied to the
     standard output with the backslash removed.  Lines beginning
     with a backslash followed by a noncontrol character are
     copied in their entirety.

     A keyword is composed of nine or less alphanumerics; the
     first must be alphabetic.  A value is any ASCII string that
     can be created with ed(1); a numeric value is an unsigned
     string of digits.  Keyword values may not contain blanks or
     tabs.

     Replacement of keywords by values is done whenever a keyword
     surrounded by control characters is encountered on a version
     control statement.  The -a keyletter (see below) forces
     replacement of keywords in all lines of text.  An
     uninterpreted control character may be included in a value
     by preceding it with \.  If a literal \ is desired, then it
     too must be preceded by \.

     Version Control Statements

     :dcl keyword[, ..., keyword]
            Used to declare keywords. All keywords must be
            declared.

     :asg keyword=value
            Used to assign values to keywords. An asg statement



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VC(1SCCS)               COMMAND REFERENCE               VC(1SCCS)



            overrides the assignment for the corresponding
            keyword on the vc command line and all previous asg's
            for that keyword.  Keywords declared, but not
            assigned values have null values.

     :if condition
              .
              .
              .  :end

            Used to skip lines of the standard input. If the
            condition is true all lines between the if statement
            and the matching end statement are copied to the
            standard output.  If the condition is false, all
            intervening lines are discarded, including control
            statements.  Note that intervening if statements and
            matching end statements are recognized solely for the
            purpose of maintaining the proper if-end matching.

            The syntax of a condition is:

                 <cond> ::= [ "not" ] <or>
                 <or> ::= <and> | <and> "|" <or>
                 <and> ::= <exp> | <exp> "&" <and>
                 <exp> ::= "(" <or> ")" | <value> <op> <value>
                 <op> ::= "=" | "!=" | "<" | ">"
                 <value> ::= <arbitrary ASCII string> | <numeric string>

            The available operators and their meanings are:

                 =    equal
                 !=   not equal
                 &    and
                 |    or
                 >    greater than
                 <    less than
                 ( )  used for logical groupings
                 Not (!)   may only occur immediately after the if, and
                      when present, inverts the value of the entire condition

            The > and < operate only on unsigned integer values
            (for example,: 012 > 12 is false).  All other
            operators take strings as arguments (for example,:
            012 != 12 is true).  The precedence of the operators
            (from highest to lowest) is:

                 = != > <  all of equal precedence & |

            Parentheses may be used to alter the order of
            precedence.

            Values must be separated from operators or



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VC(1SCCS)               COMMAND REFERENCE               VC(1SCCS)



            parentheses by at least one blank or tab.

     ::text Used for keyword replacement on lines that are copied
            to the standard output.  The two leading control
            characters are removed, and keywords surrounded by
            control characters in text are replaced by their
            value before the line is copied to the output file.
            This action is independent of the -a keyletter.

     :on

     :off   Turn on or off keyword replacement on all lines.

     :ctl char
            Change the control character to char.

     :msg message
            Prints the message on the diagnostic output.

     :err message
            Prints the  message followed by:

                 ERROR: err statement on line ... (915)

            on the diagnostic output.  Vc halts execution, and
            returns an exit code of 1.

OPTIONS
     -a     Forces replacement of keywords surrounded by control
            characters with their assigned value in all text
            lines, not just in vc statements.

     -cchar Specifies a control character to be used in place of
            the : character.

     -s     Silences warning messages (not error) that are
            normally printed on the diagnostic output.

     -t     All characters from the beginning of a line up to and
            including the first tab character are ignored for the
            purpose of detecting a control statement.  If one is
            found, all characters up to and including the tab are
            discarded.

DIAGNOSTICS
     Use sccshelp (1sccs) for explanations.

SEE ALSO
     sccshelp(1sccs).






Printed 5/12/88                                                 3

%%index%%
na:288,72;
sy:360,342;
de:702,2863;3925,2621;6906,1207;
op:8113,884;
di:8997,193;
se:9190,130;
%%index%%000000000128