Computer Programming

A batch system is one in which jobs are bundled together with the instructions necessary to allow them to be processed without intervention.

Often jobs of a similar nature can be bundled together to further increase economy

The basic physical layout of the memory of a batch job computer is shown below:

--------------------------------------

| |

| Monitor (permanently resident) |

| |

--------------------------------------

| |

| User Space |

| (compilers, programs, data, etc.) |

| |

--------------------------------------

The monitor is system software that is responsible for interpreting and carrying out the instructions in the batch jobs. When the monitor started a job, it handed over control of the entire computer to the job, which then controlled the computer until it finished.

A sample of several batch jobs might look like:

$JOB user_spec; identify the user for accounting purposes

$FORTRAN; load the FORTRAN compiler

source program cards

$LOAD; load the compiled program

$RUN; run the program

data cards

$EOJ; end of job

$JOB user_spec; identify a new user

$LOAD application

$RUN

data

$EOJ

Often magnetic tapes and drums were used to store intermediate data and compiled programs.

Advantages of batch systems

move much of the work of the operator to the computer

increased performance since it was possible for job to start as soon as the previous job finished

Disadvantages

turn-around time can be large from user standpoint

more difficult to debug program

due to lack of protection scheme, one batch job can affect pending jobs (read too many cards, etc)

a job could corrupt the monitor, thus affecting pending jobs

a job could enter an infinite loop

As mentioned above, one of the major shortcomings of early batch systems was that there was no protection scheme to prevent one job from adversely affecting other jobs.

The solution to this was a simple protection scheme, where certain memory (e.g. where the monitor resides) were made off-limits to user programs. This prevented user programs from corrupting the monitor.

To keep user programs from reading too many (or not enough) cards, the hardware was changed to allow the computer to operate in one of two modes: one for the monitor and one for the user programs. IO could only be performed in monitor mode, so that IO requests from the user programs were passed to the monitor. In this way, the monitor could keep a job from reading past it's on $EOJ card.

To prevent an infinite loop, a timer was added to the system and the $JOB card was modified so that a maximum execution time for the job was passed to the monitor. The computer would interrupt the job and return control to the monitor when this time was exceeded.

No. Variable names are best kept as short as possible so long as they remain self-explanatory. The name "cost" alone implies an amount of some kind (usually currency but not always).

Also, if a name consists of more than one word, an underscore makes it more readable. E.g., "cost_amount" would be better than "costAmount", but "cost" alone would still be better.

It's also a good idea to put variable names in namespaces unless they are local variables or class members. That way you're less likely to end up with name-clashes in the global namespace.

The QWERTY keyboard was patented by USA(207,559) issued on August 27, 1878 invited by Christopher Latham Sholes an American.

The core if it would contain lines like these:

printf ("sizeof (char)=%d\n"

"sizeof (short)=%d\n"

"sizeof (int)=%d\n"

"sizeof (long)=%d\n"

"sizeof (long long)=%d\n"

"sizeof (size_t)=%d\n"

"sizeof (void *)=%d\n"

"sizeof (ptrdiff_t)=%d\n"

"sizeof (va_list)=%d\n"

"sizeof (intptr_t)=%d\n"

, (int)sizeof (char)

, (int)sizeof (short)

, (int)sizeof (int)

, (int)sizeof (long)

, (int)sizeof (long long)

, (int)sizeof (size_t)

, (int)sizeof (void *)

, (int)sizeof (ptrdiff_t)

, (int)sizeof (va_list)

, (int)sizeof (intptr_t)

);

Extract the files from the RAR, then create the PUP file from the extracted files.

Ernest Rutherford was born on August 30, 1871

The clock crystal. remove it or break it, and you will have about 5 seconds worth of time on the fastest desktop you have ever seen, and about 5 minutes of trying to put the fire out.

Depends on the program and what you mean by "set up." It could be several seconds to several hours.

The opposite of the action "to share" would be to withhold or keep (to oneself).

(One sense of sharing is selflessness or generosity, where the opposite would be selfishness, cupidity, or avarice.)

no, Parent class can not access the members of child class ,but child class can access members of parent class

It is "google."

strcpy is meant to copy only null-terminated strings. It is probably implemented to copy every byte until it encounters a #0.

strncpy() copies n bytes and it adds null termination at the end of the target string.

When a form is opened Modal, Code execution is stopped, and the form must be closed in order for execution to continue past the point of calling "ShowModal" You have the choice of opening a form as Modal or not when you display a form.

In debug mode, many of the compiler optimizations are turned off which allow the generated executable match up with the code. This allows breakpoints to be set accurately and allows a programmer to step through the code one line at a time. Debugging information is also generated help the debugger figure out where it is in the source code.

In release mode, most of the compiler's optimizations are turned on. Chunks of your code could be completely deleted, removed, or rewritten. The resulting executable will most likely not match up with your written code. However, normally release mode will run faster then debug mode due to the optimizations.

Decision support systems help managers analyze information within the organization. Based on this information, managers can make better decisions about pricing and profitability.

Grubbs test is used to detect outliers in a univariate data set.

This depends on what compiler you are using. For the most common compilers (including gcc) on a *nix system, most standard header files will be either in /usr/include or /usr/local/include. Check your compiler's documentation for how to check and/or modify the search paths.

Two possibilities: on success, it'll return the amount of characters printed. On failure, a negative number is returned.

Ideally, only the user interface element(s) should communicate with the user.

#include<string>

#include<iostream>

std::ostream& alternate (std::ostream& os, const std::string& str) {

for (size_t index=0; index<str.size(); index+=2) os << str[index];

return os;

}

int main (void) {

std::string test {"The quick brown fox jumps over the lazy dog"};

alternate (std::cout, test);

std::cout << std::endl;

}

Output:

Teqikbonfxjmsoe h aydg

The frameset tag is used to define the layout of a web page which uses frames. It defines how many frames, their sizes, and what pages get loaded in each one. A web page which uses frames actually calls for separate web pages to load in each frame. The attributes and further description are all listed here: http://devedge-temp.mozilla.org/library/manuals/1998/htmlguide/tags11.html#1294825

maayo pa ug maghikog!

Stack pointer points to the topmost / most recently referenced location on the stack;

- Nutan