NAME
unget — undo a
previous get of an SCCS file (DEVELOPMENT)
SYNOPSIS
DESCRIPTION
The unget utility shall reverse the effect
of a get(1) -e done prior to
creating the intended new delta.
OPTIONS
The unget utility shall conform to XBD
V1_chap12(7).
The following options shall be supported:
- -r SID
- Uniquely identify which delta is no longer intended. (This would have been specified by get as the new delta.) The use of this option is necessary only if two or more outstanding get commands for editing on the same SCCS file were done by the same person (login name).
-s- Suppress the writing to standard output of the intended delta's SID.
-n- Retain the file that was obtained by get , which would normally be removed from the current directory.
OPERANDS
The following operands shall be supported:
- file
- A pathname of an existing SCCS file or a directory. If file is a
directory, the
ungetutility shall behave as though each file in the directory were specified as a named file, except that non-SCCS files (last component of the pathname does not begin with s. ) and unreadable files shall be silently ignored.If exactly one file operand appears, and it is ‘
-’, the standard input shall be read; each line of the standard input shall be taken to be the name of an SCCS file to be processed. Non-SCCS files and unreadable files shall be silently ignored.
STDIN
The standard input shall be a text file used only when the
file operand is specified as
‘-’. Each line of the text file shall
be interpreted as an SCCS pathname.
INPUT FILES
Any SCCS files processed shall be files of an unspecified format.
ENVIRONMENT VARIABLES
The following environment variables shall affect the execution of
unget:
LANG- Provide a default value for the internationalization variables that are unset or null. (See XBD 8.2 Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.)
LC_ALL- If set to a non-empty string value, override the values of all the other internationalization variables.
LC_CTYPE- Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments and input files).
LC_MESSAGES-
Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. NLSPATH- Determine the location of messages objects and message catalogs.
ASYNCHRONOUS EVENTS
Default.
STDOUT
The standard output shall consist of a line for each file, in the following format:
"%s\n", <SID removed from file>
If there is more than one named file or if a directory or standard input is named, each pathname shall be written before each of the preceding lines:
"\n%s:\n", <pathname>
STDERR
The standard error shall be used only for diagnostic messages.
OUTPUT FILES
Any SCCS files updated shall be files of an unspecified format. During processing of a file, a locking z-file, as described in get(1), and a q-file (a working copy of the p-file), may be created and deleted. The p-file and g-file, as described in get(1), shall be deleted.
EXTENDED DESCRIPTION
None.
EXIT STATUS
The following exit values shall be returned:
CONSEQUENCES OF ERRORS
Default.
APPLICATION USAGE
None.
EXAMPLES
None.
RATIONALE
None.
FUTURE DIRECTIONS
If this utility is directed to create a new directory entry that contains any bytes that have the encoded value of a <newline> character, implementations are encouraged to treat this as an error. A future version of this standard may require implementations to treat this as an error.
SEE ALSO
XBD V1_chap08(7), V1_chap12(7)
CHANGE HISTORY
First released in Issue 2.
Issue 6
The normative text is reworded to avoid use of the term "must" for application requirements.
Issue 7
SD5-XCU-ERN-97 is applied, updating the SYNOPSIS.
Issue 8
Austin Group Defect 251 is applied, encouraging implementations to disallow the creation of filenames containing any bytes that have the encoded value of a <newline> character.
Austin Group Defect 1122 is applied, changing the description of NLSPATH .