[c] How to calculate size of the file from size of the buffer?


 
Thread Tools Search this Thread
Top Forums Programming [c] How to calculate size of the file from size of the buffer?
# 1  
Old 06-14-2012
[c] How to calculate size of the file from size of the buffer?

Hi,

Can I find size of the file from size of the buffer written?
Code:
nbECRITS = fwrite(strstr(data->buffer, ";") + 1, sizeof(char), (data->buffsize) - LEN_NOM_FIC, fic_sortie);

Thank You Smilie
# 2  
Old 06-14-2012
It is not guaranteed to work. Use stat() to get a file size.
Code:
#include <sys/stat.h>
size_t filesize(int fd)
{
     struct stat st;
     if(fstat(fd, &st) == -1 )
     {
          perror("cannot stat file");
          exit(1);
      }
     return st.st_size;
}

void myfoo(void)
{
    size_t bytes;
    //.......... your code here
     bytes=filesize(fileno(fic_sortie));
    //.......  more code here
}

try something like that.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Find a particular directory in multiple file systems and calculate total size

Hello : I need some help in writing a ksh script which will find a particular directory in all the file systems in a server and finally report the total size of the direcotry in all the file systems. Some thing like this.. find /u*/app/oracle -type d -name "product" -prune and then... (1 Reply)
Discussion started by: Sam1974
1 Replies

2. UNIX for Dummies Questions & Answers

Decrease buffer size

Hi, I am using the below command to get the output in a file called "Logs.txt" tail -f filename | egrep -i "cpu | hung " >> Logs.txt The problem is the Logs.txt file gets updated only after the buffer is 8Kb, but i want to update the file immediately and not wait for the buffer to get 8kb. Is... (8 Replies)
Discussion started by: @bhi
8 Replies

3. Programming

Maximum buffer size for read()

Hi friends, Hope everybody is fine. First have a look at my code, then we will talk about it. $ cat copy.c #include <stdio.h> #define PERMS 0644 /* RW for owner, R for group, others */ #define BUFSIZE 1 char *progname; int main(int argc,char * argv) { int f1, f2, n; ... (4 Replies)
Discussion started by: gabam
4 Replies

4. UNIX for Dummies Questions & Answers

How to check the buffer size of a file?

I have a c program and I want to know what command to use to display the current buffer size of the file using Terminal in Unix? (0 Replies)
Discussion started by: Izzy123
0 Replies

5. UNIX for Dummies Questions & Answers

calculate directory size by year of file

I need to calcualte the size of a directory by the year the files in that directory were created . For example the script will sum up, by year, the number of blocks for that directory and its' subdirectories for files created / accessed in that year. I need a report that would look like... (11 Replies)
Discussion started by: igidttam
11 Replies

6. Red Hat

buffer cache size

hi everyone, can any one help change the buffer cache size in redhat and suse?? this error i got when i installed oracle 10g and it went well and when i try to mount the database using startup cmd it says too many buffer cache parameters (error code : ora-1034) thnq in advance (0 Replies)
Discussion started by: gsr_kashyap
0 Replies

7. AIX

Pipe Buffer Size

Hi:- One of our users is getting an error: "There is no process to read data written to a pipe.” I am trying to find out what the pipe buffer size is currently set to. How do I go about this? Thanks, (0 Replies)
Discussion started by: janet
0 Replies

8. Shell Programming and Scripting

How to calculate file's size in directory and subdirectory

Hi, I have written one script to calculate total space of all file in one directory, ignoring subdirectory, it works fine. Now, I've been trying to calculate all files which includes files in any subdirectories. I use recursive function to do this, but it can work only if there is only one... (4 Replies)
Discussion started by: KLL
4 Replies

9. Programming

Using fread if the buffer size is not known

Hi... I am trying to read a binary data that have different types of messages of different lengths. I am using fread() but this functions needs the size and count to read the buffer from the file. I think this may cause that the buffer overlaps other messages. Is there an alternative to read... (1 Reply)
Discussion started by: jlrodz
1 Replies

10. UNIX for Dummies Questions & Answers

how to calculate the file size?

HI, Can somebody please tell me how many bytes make a KB & MB. ThANKS. Rooh.:( (3 Replies)
Discussion started by: rooh
3 Replies
Login or Register to Ask a Question