NAME

delta − make a delta (change) to an SCCS file

USAGE

delta /-r [ SID ] [ −s ] [ −n ] [ −glist ] [ −m [ mrlist ]] [ −y [ comment ]] [ −p ] files

DESCRIPTION

Delta permanently introduces into the named SCCS file changes made to the file retrieved by get(1) (called the g-file, or generated file).

Delta makes a delta to each named SCCS file.  If a directory is named, delta behaves as though each file in the directory were specified as a named file, except that it silently ignores non-SCCS and unreadable files.  If you specify a dash (−) in place of a filename, it reads from the standard input, interpreting each line as the name of an SCCS file to be processed. 

Delta issues prompts on the standard output, depending on the presence of certain options in the SCCS file.  See admin(1) for more information. 

OPTIONS

The options described below apply independently to each named file. 

−rSID Uniquely identify which delta is to be made to the SCCS file.  This option is necessary only if two or more outstanding get commands for editing (get −e) on the same SCCS file are done by the same person (log-in name).  The SID value specified with this keyletter is either the SID specified on the get command line or the SID to be made as reported by the get(1) command.  If the specified SID is ambiguous or if it was omitted when it was required to be present, a diagnostic results. 

−s Do not print the created delta’s SID or the number of lines inserted, deleted, and unchanged in the SCCS file on standard output. 

−n Retain the edited g-file normally removed at completion of delta processing. 

−glist Specify a list of deltas to be ignored when the file is accessed at the change level (SID) created by this delta.  See get(1) for the definition of list. 

−m [mrlist] If the SCCS file has the v flag set, then a Modification Request (MR) number must be supplied as the reason for creating the new delta.  See admin(1) for more information.  If −m is not used and the standard input is a terminal, the prompt “MRs?” is issued on the standard output before the standard input is read; if the standard input is not a terminal, no prompt is issued.  This particular prompt always precedes the prompt for comments (see the −y option).  MRs in a list are separated by blanks and/or tab characters.  An unescaped newline character terminates the MR list.  Note that if the v flag has a value, it is taken to be the name of a program (or Shell procedure) that validates the correctness of the MR numbers.  If a non-zero exit status is returned from the MR number validation program, delta assumes that the MR numbers were not all valid, and it terminates. 

−y [comment]
Specify arbitrary text to describe the reason for making the delta. A null string is considered a valid comment.  If −y is not specified and the standard input is a terminal, the prompt “comments?” is issued on the standard output before the standard input is read.  If the standard input is not a terminal, no prompt is issued.  An unescaped newline character terminates the comment text. 

−p On the standard output, print the SCCS file differences before and after the delta is applied.  Use a diff(1) format. 

CAUTIONS

Lines beginning with an SOH ASCII character (binary 001) cannot be placed in the SCCS file unless the SOH is escaped.  This character has special meaning to SCCS and will cause an error if it is not escaped.  Refer to sccsfile(4) for more information. 

Avoid a get of many SCCS files, followed by a delta of those files, when the get generates a large amount of data.  Instead, multiple get/delta sequences should be used. 

If you specify the standard input on the delta command line, you must use the −m and/or −y keyletters. 

Comments are limited to text strings of 512 characters. 

FILES

g-file Existed before the execution of delta; removed after completion of delta. 

p-file Existed before the execution of delta; may exist after completion of delta. 

q-file Created during the execution of delta; removed after completion of delta. 

x-file Created during the execution of delta; renamed to SCCS file after completion of delta. 

z-file Created during the execution of delta; removed during the execution of delta. 

d-file Created during the execution of delta; removed after completion of delta. 

/usr/bin/bdiff Program to compute differences between the “gotten” file and the g-file.

DIAGNOSTICS

Use help(1) for explanations. 

RELATED INFORMATION

admin(1), bdiff(1), cdc(1), get(1), help(1), prs(1), rmdel(1), sccsfile(4).