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Reading a file

Experts,
I need to read from a file fo this format..Please let me know how to do this..

a
Name1
Name2
Name3
//each segment seperated by a space
m
Date1
Date2
Date3

the and m signal the start of a command. I need to put all the elements associated with a particualr command in a vector for processing. There is no limit of how many of these segments are available, but there will be a bland line after the last command set to signal the end of the file.

Irish97

ASKER

I am sorry..I forgot to to confirm that each element has to be read as a string..ie..a, Name1, Name2, Name3 and Name4 need to be read into a vector and the same for the m command.

ASKER CERTIFIED SOLUTION

sumant032199

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nietod

>> you can use read function or fread function
>> and give the sizeof(your_struct) as a parameter
>> in place of no of bytes to be read
It sounds like the date is stored in ASCII. a binary read would not be a good idea. You'll read the newlines. Besides its unlikey that each line is the same size.

>> fread() will be more useful if the file is ASCII (readable)
Why? Both are used to ready data in binary form?

nietod

class CmdDat
{
private:
char CmdLtr; // Command letter
vector<string> CmdPrm; // Command parameters.
public:
// some member accces functions, maybe a constructor or two.

friend istream &operator >> (istream &In,CmdDat &Dat);
};

istream &operator >> (istream &In,CmdDat &Dat)
{
string Lin;

// Look for command letter.
while (true)
{
getline(In,Lin);

int Pos = Lin.find_first_not_of(' '); // Look for first non-space char.
if (Pos != basic_string::npos) // If there is a non-space char.
{
Dat.CmdLtr = Lin[Pos]; // Set the command letter.
break;
}
}

// Get parameter lines until a blank line.
while (true)
{
getline(In,Lin); // Get the next line.

if (Lin.length() == 0) // If the line is empty.
break; // Stop getting parameter lines.
Dat.CmdPrm.push_back(Lin); // Add the command parameter to the list.
}

return In;
}

sumant032199

Instead of fread() I wanted to say
fscanf();