Boosting Your e3000 Productivity
MPE for UNIX Users:
Examining File Content
By Robert Green, Robelle
Last month in
Part 3 of our series, we looked at files. This month we learn how to
look at file content. If you are a Unix person, the first thing you
look for is more, and the MPE equivalent is Print:
displays the lines of the file on $Stdlist, stopping every screenful
and asking if you want more. You can answer Y or N. In Unix, you
usually press Space for Yes or go on, but in MPE you
usually press Enter.
Print is only
useful for files of text data. For looking at binary data, the basic
tool provided by MPE is Fcopy.
purpose of Fcopy is file copy, but it can also display
binary data in Hex or Octal format and do some simple data selection.
Fcopy is a subsystem, while Print was an MPE command. You enter the
subsystem with the Fcopy command and it has its own commands. You
exit the subsystem with the Exit command (some later subsystems used
Quit as Unix started to influence MPE). Other subsystems of MPE
include Editor and Sort.
when you enter Fcopy, the prompt character changes from Colon to
Greater Than. This is typical a Colon prompt always indicates
that an MPE command is expected.
command displays each record of filename on $Stdlist as a hexadecimal
dump and as a character dump (Char replaces nonprinting characters
such as Carriage Return and Linefeed with Period to avoid disrupting
command converts the record data to Octal instead of Hex. The third
command, Exit, gets you back to MPE.
introduces you to a couple of other MPE-isms. You use Control-Y to
stop the listing; this is true for all MPE subsystems, but for MPE
commands use the Break key if Control-Y does not work. The syntax of
the Fcopy commands is different from that of MPE commands;
unfortunately, this is true of most all MPE subsystems they
all have slightly different command syntax styles.
allows you to select specific records numbers, or records that have a
specific text string at a given location. You append the Subset
option to your copy task:
subset=string, column [,EXCLUDE]
cannot select on binary fields or look for multiple strings.
text searches, the Unix user turns to grep, and MPE has grep in the
Posix shell. To enter the shell, you type sh.pub.sys,
which is an implied run on the sh program in the
pub group of the sys account. When you are
in the Posix shell, you must use Posix filenames, not MPE filenames.
So sh.pub.sys would be /SYS/PUB/SH.
at file contents, the Posix head and tail commands are very handy
(show the start of a file or the end of it). Another MPE subsystem
that can be used for examining text files is Editor.
the prompt character is Slash, while Fcopy used Greater Than.
Editor has a
fairly powerful set of search options. In this example, Find looks
for the next line that contains the string at any location within the
line. But to find all the lines that match, you must program the Find
in a While loop.
MPE also has
a wide variety of text tools from third-parties that you will likely
want on your system, such as our own Qedit, an Editor replacement
that also provides full-screen editing (see www.qedit.com).
commands are similar to Editors, but the default behavior is to
treat any occurrence of a string as a request for all the lines that
contain that string. Qedit borrows concepts from Fcopy and other
tools. For example, you can display the selected lines in Hexadecimal
if you wish: /list $hex $char 1/10
case and only search certain columns on string matches: /List
enhancement (Upshift 20/50)
Or search for
up to 10 strings on a single command: /List problem or
bug or help
Magnet is our
method of choice for searching a group of files, because it is so
fast. It is a part of Nuggets (aka Toolboxes), a package of MPE
utilities written by Stan Sieler and friends, and sold by Lund. By
default, Magnet lists the files with a filecode of zero (regular
files) or 111 (Qedit files) in your logon group that contain at least
one line with the target string. Use the -F option to specify
filesets, the -C option to ignore case, -L to list lines that match,
and -E to show Editor-style line numbers.
For example, to search
the SRC group of the logon account for fopen, ignoring
case, you would use the command :magnet -f@.src fopen -c -l
e. (For more details on Magnet, see www.allegro.com/products/hp3000/toolboxes.html)
MPEX is a
third-party tool from Vesoft that extends the MPE command shell to
work on sets of many files, rather than just one file. It is very
flexible and allows selections such as files bigger than 1 GB
and untouched in over a year. MPEX allows you to select files
based on searching text within the files:
MPEX also allows
searching for lines containing alternate strings, or more than one
string, or almost any search logic:
@.SOURCE;SEARCH=PROCEDURE or FUNCTION;NUM
@.SOURCE;SEARCH=PROCEDURE and FNAME
@.JOB;SEARCH=!JOB and NOT MANAGER.SYS
many more options (case-less, look for delimiters, look for a
delimiter on the left only, etc.).
What does it
mean when you get the error below?
VIOLATION (FSERR 45)
The PRINT command
failed. (CIERR 9080)
This means is
that you tried to open a database file in user-mode. These are
privileged files that can only be opened in Priv Mode.
This restriction ensures the integrity of the database structure by
forcing all access through system-approved tools or APIs.
Query is a
database tool found on every HP 3000. It can do selection, but only
works on databases, not disk files. A simple Query task would be:
order-detail.order-date GT 20040101
numerous report formatting options, including sorting, level breaks,
item formatting, etc. However, the output is intended for a printer,
so most of the formatting options have that in mind. It is possible
to redirect this output to a disk file, but Query was written before
anyone asked for output to an Excel spreadsheet.
Suprtool is our
third-party product (see
www.suprtool.com) that is found on many HP 3000 systems; it works
on both databases and disk files. Like Fcopy it can copy or print
records using Char,hex dump, but it can do much, much more. It can do
sophisticated selection and sort the records. For example, to select
all the Open orders, sort them, eliminate duplicates, write them to a
disk file for further processing, and print the fields of each
selected entry, use:
> 20040101 and order-status=O
provides a Define and Item command to describe the record format of a
file so that it can be treated like a database. Or to more accurately
describe a database (i.e., define sub-fields, date fields, and
decimal places). The output can go to the printer, or to a disc file,
or to the database, or to an Excel spreadsheet, or to almost any
other format of file.
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