synchronous
Regular. Most communication within a computer system is synchronous, controlled by the computer's own internal clock, while communication between computers is usually asynchronous. Synchronous telecommunications are, however, becoming more widely used.


--------------------------------------------------
Note added at 10 mins (2005-05-18 23:43:28 GMT)
--------------------------------------------------

Synchronous \\Syn\"chro*nous\\, a. [Gr. ?; sy`n with + ? time. Cf.
Chronicle.]
Happening at the same time; simultaneous. --
Syn\"chro*nous*ly, adv.
[1913 Webster]
synchronous - WordNet (r) 2.0 (August 2003) :
adj 1: occurring or existing at the same time or having the same period or phase; \"recovery was synchronous with therapy\"- Jour.A.M.A.; \"a synchronous set of clocks\";
\"the synchronous action of a bird\'s wings in flight\";
\"synchronous oscillations\" [syn: synchronal,
synchronic] [ant: asynchronous]
2: (digital communication) pertaining to a transmission
technique that requires a common clock signal (a timing
reference) between the communicating devices in order to
coordinate their transmissions [ant: asynchronous]
synchronous - Free On-line Dictionary of Computing (19 Sep 2003) :
synchronous
<operating system, communications> 1. Two or more processes
that depend upon the occurrences of specific events such as
common timing signals.
2. Occurring at the same time or at the same rate or with a
regular or predictable time relationship or sequence.
Opposite: asynchronous.
http://onlinedictionary.datasegment.com/word/synchronous

Answers coming....

--------------------------------------------------
Note added at 10 mins (2005-05-18 23:43:54 GMT)
--------------------------------------------------

Perhaps this all might help to make it clearer:

Synonyms: contemporary, contemporaneous, simultaneous, synchronous, concurrent, coincident, concomitant
These adjectives mean existing or occurring at the same time. Contemporary is used more often of persons, contemporaneous of events and facts: The composer Salieri was contemporary with Mozart. A rise in interest rates is often contemporaneous with an increase in inflation.
Simultaneous more narrowly specifies occurrence of events at the same time: The activists organized simultaneous demonstrations in many major cities.
Synchronous refers to correspondence of events in time over a short period: The dancers executed a series of synchronous movements.
Concurrent implies parallelism in character or length of time: The mass murderer was given three concurrent life sentences.
Coincident applies to events occurring at the same time without implying a relationship: \"The resistance to the Pope\'s authority . . . is pretty nearly coincident with the rise of the Ottomans\" John Henry Newman.
Concomitant refers to coincidence in time of events so clearly related that one seems attendant on the other: He is an adherent of Freud\'s theories and had a concomitant belief in the efficacy of psychoanalysis.
Usage Note: When contemporary is used in reference to something in the past, its meaning is not always clear. Contemporary critics of Shakespeare may mean critics in his time or critics in our time. When the context does not make the meaning clear, misunderstanding can be avoided by using phrases such as critics in Shakespeare\'s time or modern critics.

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company.
Updated in 2003. Published by Houghton Mifflin Company. All rights reserved.
ThesaurusLegend: Synonyms Related Words Antonyms
Noun 1. contemporary - a person of nearly the same age as another
coeval
compeer, equal, peer, match - a person who is of equal standing with another in a group
Adj. 1. contemporary - characteristic of the present; \"contemporary trends in design\"; \"the role of computers in modern-day medicine\"
modern-day
modern - belonging to the modern era; since the Middle Ages; \"modern art\"; \"modern furniture\"; \"modern history\"; \"totem poles are modern rather than prehistoric\"
2. contemporary - belonging to the present time; \"contemporary leaders\"
present-day
current - occurring in or belonging to the present time; \"current events\"; \"the current topic\"; \"current negotiations\"; \"current psychoanalytic theories\"; \"the ship\'s current position\"
3. contemporary - occurring in the same period of time; \"a rise in interest rates is often contemporaneous with an increase in inflation\"; \"the composer Salieri was contemporary with Mozart\"
contemporaneous
synchronal, synchronic, synchronous - occurring or existing at the same time or having the same period or phase; \"recovery was synchronous with therapy\"- Jour.A.M.A.; \"a synchronous set of clocks\"; \"the synchronous action of a bird\'s wings in flight\"; \"synchronous oscillations\"

While Charlie and Balasubramaniam have explained the difference between synchronous and asynchronous communications, I would suggest that

a) in this instance, when talking about (potentially) concurrent events, the "communications" definition does not apply, and synchronous means what it appears to mean: simultaneous, at the same time, in tandem -- which makes little sense in the context

b) the author actually meant "synchronized" instead of "synchronously" in the first sentence (in the second sentence he/she did in fact use this term)

In multi-threaded programming, "synchronized execution" means that only one thread (process) has access to a certain resource (or connected set of resources) at a time.

A monitoring instance makes sure that if one process has already been granted access to that "synchronized" set of resources, a second process does not get access until the first process has returned "the key" to those resources, i.e. has finished execution.

More specifically, if a set of methods (structural units of a computer program; the scripts in your text could be considered as analogous to methods from the point of view of the operating system which executes them) is synchronized, only one of them can run at a time. Which is what the author has in fact already stated with "one at a time", only to confuse us with "synchronously".

As an aside: in German you'd write "synchronisiert". "Synchron" would be plain wrong.

--------------------------------------------------
Note added at 8 hrs 30 mins (2005-05-19 08:03:43 GMT)
--------------------------------------------------

It\'s not easy to find a link with a comprehensible explanation, but let\'s try:
http://www.allapplabs.com/interview_questions/java_interview...
(Questions 2 and 12)

http://www.cs.williams.edu/~andrea/cs136/Lectures/Lec35/Lec3...

It appears that only one startup and shutdown script can be active at a time, while many login-logoff scripts can be running simultaneously (that is, at the same time).

The comparision is usually between synchronous and asynchronous.

Synchronus means the two process are somewhat locked and happen in tandem.

The usual example given in textbooks to contrast between synchronous and asynchronous processes is between (a telephone conversation, which is synchronous) and an email (which is asynchronous).

The telephone conversation happens in a set fashion, the sender dials a number, the connection is established, the phone rings, the answerer lifts the phone, and the conversation takes place, with one person speaking at a time. All this happens in a proper sequence, the order cannot be changed.

In contrast, in an email, the message flows through the network following whichever path is available to it, you can send a message to the sender even before you have received his reply, you can even send a message when the receiver is not logged in. This is asynchronous, that is no rhythm is established between the sender and the receiver, or between the two processes.

Here simultaneously seems to have been used in the meaning of asynchronous.

--------------------------------------------------
Note added at 3 hrs 14 mins (2005-05-19 02:47:27 GMT)
--------------------------------------------------

May be in your translation you can use the equivalents in your target language for \"one at a time\" and \"many at a time\" in place of \"synchrously\" and \"simultaneously\".

--------------------------------------------------
Note added at 3 hrs 20 mins (2005-05-19 02:53:09 GMT)
--------------------------------------------------

Probably there are two types of scripts. Those scripts of which only one instance can be active at a time(the operating system is an example, there can be only one operating system active at a time).

There are other scripts in whose case, many instances of the same script can be active at the same time (The Word program is an example, you can have any number of documents open at a time.)

The words \"synchronous\" and \"simultaneously\" are perhaps trying to explain these two types of scripts.

--------------------------------------------------
Note added at 10 hrs 2 mins (2005-05-19 09:35:38 GMT)
--------------------------------------------------

In the light of Endre\'s comment, I think what synchronous means here is \"mutually exclusive\" that is, if one process of this type is running, then another process of the same type will have to wait till the running process is finished, or its own priority rating goes up and it becomes the top priority process, in which case the operating system can switch to this process.


Probably the author thought terms like \"mutually exclusive\" were computer jargon and sought to simplify matters by using a more familiar term like synchronous, but blotched up badly in the process.

--------------------------------------------------
Note added at 10 hrs 5 mins (2005-05-19 09:38:06 GMT)
--------------------------------------------------

I would rephrase in this manner:

Startup and shutdown scripts run in a mutually exclusive manner in order of priority.

Unlike startup and shutdown scripts, however, logon and logoff scripts are not mutually exclusive and can run simultaneously...