delta - Saves editing changes in a Source Code Control
System (SCCS) file
delta [-g list] [-m MRlist] [-n] [-p] [-s] [-r SID] [-y
[comment]] file... | -
Interfaces documented on this reference page conform to
industry standards as follows:
delta: XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information
about industry standards and associated tags.
Specifies a list of SIDs (deltas) that are to be ignored
when the get command creates the g-file. After you use
this option, get ignores the deltas in this list when it
builds the g-file. Specifies a Modification Request (MR)
number as the reason for creating the new delta.
If the SCCS file has the v header flag set, then a
MR number must be provided. If you specify -m, the
MRs are taken from MRlist.
If you do not specify the -m option, delta reads
MRs from the standard input. If standard input is
a terminal, delta prompts you for the MRs. The
delta command continues to take input until it
reads End-of-File or an unescaped newline character.
It always reads MRs before the comments (see
the -y option). You can use spaces, tab characters,
or both to separate MRs in a list.
If the v header flag has a value, it is interpreted
as the name of a program that validates the MR numbers.
If delta returns a nonzero exit value from
the MR validation program, delta assumes some of
the MR numbers were invalid and stops running.
Retains the g-file, which is normally removed at
completion of delta processing. Writes to standard
output (in the format of the sccsdiff command) the
SCCS file differences before and after the delta is
applied. (See the sccsdiff(1) reference page for
more information.) Specifies which delta is to be
made to the SCCS file. You must use this option
only if two or more outstanding get -e commands
were done on the same SCCS file by the same person.
The SID can be either the SID specified on the get
command line or the SID to be made as reported by
the get command. An error results if the specified
SID cannot be uniquely identified, or if a SID must
be specified, but it is not. Suppresses the information
normally written to standard output on normal
completion of the delta command. Specifies
text used to describe the reason for making the
delta. A null string is considered a valid comment.
If your comment line includes special characters or
spaces, the line must be enclosed in single or double
If you do not specify -y, delta reads comments from
the standard input. If the last character of a line
is a \ (backslash), it prompts for further comments.
This way, comments could be entered as many
lines till 512 characters. (This \ is not included
in the comment). The comment terminates when it
encounters a newline or End-of-File.
The path name of an existing SCCS file or directory.
If you specify a directory in place of file, delta
performs the requested actions on all SCCS files
within that directory (that is, on all files with
the s. prefix).
If you specify a - (dash) in place of file, delta
reads standard input and interprets each line as
the name of an SCCS file. When delta reads standard
input, you must supply the -y option. You
must also supply the -m option if the v header flag
is set. (For more information on header flags, see
the admin(1) reference page.) The delta command
reads standard input until it reaches End-of-File.
The delta command reads the g-files that correspond to the
specified files (see the get(1) reference page) and creates
a new delta.
The delta command introduces into the named SCCS file any
changes that were made to the file version retrieved by an
SCCS get -e command.
[Tru64 UNIX] Avoid a get of many SCCS files followed by a
delta of those files when the get generates a large amount
of data. Instead, alternate the use of get and delta.
To use the delta command, do the following: Use get -e to
get an editable version of the file. Edit that file. Use
delta to create a new version of the SCCS file.
[Tru64 UNIX] The delta command prompts you for comments.
The comments are for that particular delta and appear in
the SCCS file header. The comments are not retrieved when
you get the delta and do not appear in the text of a
retrieved file. Use comments to keep track of why a delta
[Tru64 UNIX] To see the comments, use an editor to look
at the SCCS file, write the SCCS file to the display
screen with the cat command, or print selected parts of
the file to standard output using the prs command. Remember
not to change the contents of the SCCS file directly.
To change the delta comments, use the cdc(1) command.
[Tru64 UNIX] SCCS does not allow use of the delta command
if an editable file does not exist. However, once an
editable file exists (created with get -e), SCCS creates
the delta without checking the data being stored in the
Do not use the delta command on a file if it contains
expanded identification keywords. Read-only file versions
replace keywords with text values. Using delta on a readonly
file causes the keywords to be lost. If this happens,
remove the delta with the rmdel command or reedit
the file and replace the identification keywords. SCCS
does not allow you to use delta unless an editable copy of
the file exists.
To prevent the loss of keywords, use the admin command
with the -f option to specify the i option.
Lines beginning with an SOH ASCII character (binary 001)
cannot be placed in the SCCS file unless the SOH character
is quoted using a \ (backslash). The SOH has special
meaning to SCCS and causes an error. See the sccsfile(4)
The following exit values are returned: Successful completion.
An error occurred.
To record changes you have made to an SCCS file, enter:
This adds a delta to the SCCS file s.prog.c,
recording the changes made by editing prog.c. The
delta command then asks you for a comment that summarizes
the changes you made. Enter the comment,
then press the End-of-File key sequence or press
<Return> twice to indicate that you have finished
the comment. To record changes to an SCCS file and
specify the comment for the delta on the command
line, enter: delta s.prog.c -y "Updated calendar
function for 1993."
ENVIRONMENT VARIABLES [Toc] [Back]
The following environment variables affect the execution
of delta: Provides a default value for the internationalization
variables that are unset or null. If LANG is unset
or null, the corresponding value from the default locale
is used. If any of the internationalization variables contain
an invalid setting, the utility behaves as if none of
the variables had been defined. If set to a non-empty
string value, overrides the values of all the other internationalization
variables. Determines the locale for the
interpretation of sequences of bytes of text data as characters
(for example, single-byte as opposed to multibyte
characters in arguments and input files). Determines the
locale for the format and contents of diagnostic messages
written to standard error. Determines the location of
message catalogues for the processing of LC_MESSAGES.
Commands: admin(1), bdiff(1), cdc(1), comb(1), get(1),
prs(1), rmdel(1), sact(1), sccs(1), sccsdiff(1), sccshelp(1), unget(1), val(1), what(1)
Programming Support Tools
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