FREAD(3) Linux Programmer's Manual FREAD(3)NAME
fread, fwrite - binary stream input/output
SYNOPSIS
#include <stdio.h>
size_t fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
size_t fwrite(const void *ptr, size_t size, size_t nmemb,
FILE *stream);
DESCRIPTION
The function fread() reads nmemb elements of data, each size bytes long, from the stream pointed to by stream, storing them at the location
given by ptr.
The function fwrite() writes nmemb elements of data, each size bytes long, to the stream pointed to by stream, obtaining them from the
location given by ptr.
For nonlocking counterparts, see unlocked_stdio(3).
RETURN VALUE
fread() and fwrite() return the number of items successfully read or written (i.e., not the number of characters). If an error occurs, or
the end-of-file is reached, the return value is a short item count (or zero).
fread() does not distinguish between end-of-file and error, and callers must use feof(3) and ferror(3) to determine which occurred.
CONFORMING TO
C89, POSIX.1-2001.
SEE ALSO read(2), write(2), feof(3), ferror(3), unlocked_stdio(3)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 1996-05-17 FREAD(3)
Check Out this Related Man Page
FREAD(3) Linux Programmer's Manual FREAD(3)NAME
fread, fwrite - binary stream input/output
SYNOPSIS
#include <stdio.h>
size_t fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
size_t fwrite(const void *ptr, size_t size, size_t nmemb,
FILE *stream);
DESCRIPTION
The function fread() reads nmemb elements of data, each size bytes long, from the stream pointed to by stream, storing them at the location
given by ptr.
The function fwrite() writes nmemb elements of data, each size bytes long, to the stream pointed to by stream, obtaining them from the
location given by ptr.
For nonlocking counterparts, see unlocked_stdio(3).
RETURN VALUE
On success, fread() and fwrite() return the number of items read or written. This number equals the number of bytes transferred only when
size is 1. If an error occurs, or the end of the file is reached, the return value is a short item count (or zero).
fread() does not distinguish between end-of-file and error, and callers must use feof(3) and ferror(3) to determine which occurred.
CONFORMING TO
C89, POSIX.1-2001.
SEE ALSO read(2), write(2), feof(3), ferror(3), unlocked_stdio(3)COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2012-03-30 FREAD(3)
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)
I use a standard C source to access large files in a 32 bit environment.
I've replaced fopen, fwrite and fread by fopen64, fwrite64 and fread64.
First I did a test only replacing fopen by fopen64, it compiled without any other changes to my compilation options.
The program crashed on a write, as... (3 Replies)
Hi All,
These are the two ways i tried to read file but i getting work with second one not with the first.
char buf; // Defining space for buf
ctrlfnum = fopen(filename_arr.control_fname,"r");
1) n = fread(buf,sizeof(buf),1,ctrlfnum); ============== (not works)
2) n =... (4 Replies)
Hello All,
I tried to test a sample fread example to read a complete file
and the code is
#include <stdio.h>
#include <stdlib.h>
int main () {
FILE * pFile;
long lSize;
char * buffer;
size_t result;
pFile = fopen ( "test.xml" , "rb" );
if (pFile==NULL) {fputs ("File... (11 Replies)
When fread is used twice, the second time it seems to overwrite the first time's output. Is there any way to clear fread's internal buffer after each use ?
char *FILEREAD(const char *FILENAME)
{
static char READBUFFER = "";
READBUFFER = '\0'; // try to solve the problem but this will not... (2 Replies)
hi guys.
can we use fread and fwrite with pipes to write data more than PIPE_BUF atomically since they lock FILE object until I/O operation finish? (1 Reply)
Hello,
I have a question about what happens when I copy the file which is being written by another process on Solaris 9/SPARC, UFS file system.
in particular, I want to know what happens while some process is reading the file using fread or mmap, another process try to write something on the... (4 Replies)
Hello,
I am trying to read a text file into linked list, but always got the first and last records wrong.
1) The problem looks related to the initialization of the node temp with malloc(), but could not figure it out. No error/warning at compiling, though.
2) The output file is empty,... (10 Replies)