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digitalmars.D - how to save / load files with D

reply clayasaurus <clayasaurus_member pathlink.com> writes:
hello, i'm wondering what is the best way to save / load files in D. Right now
i'm  using fopen fread fwrite and ftell to save and load files like this

int main(char[][] argv)
{
int bob = 7;

cTest test = new cTest(4,4,4);

FILE *pFile;

// write file
pFile = fopen("testio","wb"); // open new file for writing
fwrite(&bob, (ftell(pFile)+1), int.sizeof, pFile);
fwrite(test, (ftell(pFile)+1), cTest.sizeof, pFile);
fclose(pFile); // close file


// change values
bob = 8;
printf("%d\n", bob);

test = new cTest(5,6,7);
test.print();


// read file
pFile = fopen("testio","rb"); // openfile for reading
fread(&bob, (ftell(pFile)+1), int.sizeof, pFile);
fread(test, (ftell(pFile)+1), cTest.sizeof, pFile);
fclose(pFile);

printf("%d\n", bob);
test.print();

return 0;
}

are there some built in D features to make saving/loading to files easier : ) or
do i pretty much have it down? Also, for some reason i get a seg fault if i just
try to read a file without calling the write file function and i can't figure
out why. i need to find a reliable save / load method. 
May 14 2004
next sibling parent "Walter" <newshound digitalmars.com> writes:
You can do it just as you would in C, or you can use std.file.read() and
std.file.write().
May 14 2004
prev sibling parent reply J C Calvarese <jcc7 cox.net> writes:
clayasaurus wrote:
 hello, i'm wondering what is the best way to save / load files in D. Right now
 i'm  using fopen fread fwrite and ftell to save and load files like this

I don't know if it's the best way, but I usually use std.stream: http://www.digitalmars.com/d/phobos.html#stream Here's an example of reading in a file: http://www.dsource.org/tutorials/index.php?show_example=28
 int main(char[][] argv)
 {
 int bob = 7;
 
 cTest test = new cTest(4,4,4);
 
 FILE *pFile;
 
 // write file
 pFile = fopen("testio","wb"); // open new file for writing
 fwrite(&bob, (ftell(pFile)+1), int.sizeof, pFile);
 fwrite(test, (ftell(pFile)+1), cTest.sizeof, pFile);
 fclose(pFile); // close file
 
 
 // change values
 bob = 8;
 printf("%d\n", bob);
 
 test = new cTest(5,6,7);
 test.print();
 
 
 // read file
 pFile = fopen("testio","rb"); // openfile for reading
 fread(&bob, (ftell(pFile)+1), int.sizeof, pFile);
 fread(test, (ftell(pFile)+1), cTest.sizeof, pFile);
 fclose(pFile);
 
 printf("%d\n", bob);
 test.print();
 
 return 0;
 }
 
 are there some built in D features to make saving/loading to files easier : )
or
 do i pretty much have it down? Also, for some reason i get a seg fault if i
just
 try to read a file without calling the write file function and i can't figure
 out why. i need to find a reliable save / load method. 

-- Justin (a/k/a jcc7) http://jcc_7.tripod.com/d/
May 14 2004
parent reply clayasaurus <clayasaurus_member pathlink.com> writes:
In article <c8446u$2jb7$1 digitaldaemon.com>, J C Calvarese says...
clayasaurus wrote:
 hello, i'm wondering what is the best way to save / load files in D. Right now
 i'm  using fopen fread fwrite and ftell to save and load files like this

I don't know if it's the best way, but I usually use std.stream: http://www.digitalmars.com/d/phobos.html#stream Here's an example of reading in a file: http://www.dsource.org/tutorials/index.php?show_example=28

Ok, I've decided to use the std.stream as well. However, there is a slight problem. Why doesn't the std.stream support reading and writing the 'bit' data type? I could just use an int, but I'd rather use bit because it is smaller.
May 15 2004
parent J Anderson <REMOVEanderson badmama.com.au> writes:
clayasaurus wrote:

In article <c8446u$2jb7$1 digitaldaemon.com>, J C Calvarese says...
  

clayasaurus wrote:
    

hello, i'm wondering what is the best way to save / load files in D. Right now
i'm  using fopen fread fwrite and ftell to save and load files like this
      

http://www.digitalmars.com/d/phobos.html#stream Here's an example of reading in a file: http://www.dsource.org/tutorials/index.php?show_example=28

Ok, I've decided to use the std.stream as well. However, there is a slight problem. Why doesn't the std.stream support reading and writing the 'bit' data type? I could just use an int, but I'd rather use bit because it is smaller.

a stream without adding padding. Of course bit-arrays are a different story all together. -- -Anderson: http://badmama.com.au/~anderson/
May 15 2004