fread
Remonter à Stdio.h - Index
Header File
stdio.h
Category
Input/output Routines
Prototype
size_t fread(void *ptr, size_t size, size_t n, FILE *stream);
Description
Reads data from a stream.
fread reads n items of data each of length size bytes from the given input stream into a block pointed to by ptr.
The total number of bytes read is (n * size).
Return Value
On success fread returns the number of items (not bytes) actually read.
On end-of-file or error it returns a short count (possibly 0).
Example
#include <string.h>
#include <stdio.h>
int main(void)
{
FILE *stream;
char msg[] = "this is a test";
char buf[20];
if ((stream = fopen("DUMMY.FIL", "w+"))
== NULL)
{
fprintf(stderr, "Cannot open output file.\n");
return 1;
}
/* write some data to the file */
fwrite(msg, strlen(msg)+1, 1, stream);
/* seek to the beginning of the file */
fseek(stream, SEEK_SET, 0);
/* read the data and display it */
fread(buf, strlen(msg)+1, 1, stream);
printf("%s\n", buf);
fclose(stream);
return 0;
}
Portability
POSIX | Win32 | ANSI C | ANSI C++ |
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