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fread(3C)		 Standard C Library Functions		     fread(3C)

NAME
       fread - binary input

SYNOPSIS
       #include	<stdio.h>

       size_t fread(void *ptr, size_t size, size_t nitems, FILE	*stream);

DESCRIPTION
       The  fread()  function  reads  into  the	 array pointed to by ptr up to
       nitems elements whose size is specified by  size	 in  bytes,  from  the
       stream  pointed	to  by stream. For each	object,	size calls are made to
       the fgetc(3C) function and the results stored, in the order read, in an
       array of	unsigned char exactly overlaying the object. The file-position
       indicator for the stream	(if defined) is	 advanced  by  the  number  of
       bytes successfully read.	If an error occurs, the	resulting value	of the
       file-position indicator for the stream is unspecified. If a partial el-
       ement is	read, its value	is unspecified.

       The fread() function may	mark the st_atime field	of the file associated
       with stream for update. The st_atime field will be marked for update by
       the  first  successful  execution  of fgetc(3C),	fgets(3C), fgetwc(3C),
       fgetws(3C), fread(), fscanf(3C),	getc(3C),  getchar(3C),	 gets(3C),  or
       scanf(3C)  using	 stream	that returns data not supplied by a prior call
       to ungetc(3C) or	ungetwc(3C).

RETURN VALUES
       Upon successful completion, fread() returns the number of elements suc-
       cessfully  read,	which is less than nitems only if a read error or end-
       of-file is encountered. If size or nitems is 0, fread() returns	0  and
       the contents of the array and the state of the stream remain unchanged.
       Otherwise, if a read error occurs, the error indicator for  the	stream
       is set and errno	is set to indicate the error.

ERRORS
       Refer to	fgetc(3C).

EXAMPLES
       Example 1: Reading from a Stream

       The  following  example	reads a	single element from the	fp stream into
       the array pointed to by buf.

       #include	<stdio.h>
       ...
       size_t bytes_read;
       char buf[100];
       FILE *fp;
       ...
       bytes_read = fread(buf, sizeof(buf), 1, fp);
       ...

USAGE
       The ferror() or feof() functions	must be	used to	distinguish between an
       error condition and end-of-file condition. See ferror(3C).

       Because	of  possible  differences in element length and	byte ordering,
       files written using fwrite(3C) are application-dependent, and  possibly
       cannot  be read using fread() by	a different application	or by the same
       application on a	different processor.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       read(2),	 fclose(3C),  ferror(3C),   fopen(3C),	 getc(3C),   gets(3C),
       printf(3C), putc(3C), puts(3C), attributes(5), standards(5)

SunOS 5.10			  24 Jul 2002			     fread(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | EXAMPLES | USAGE | ATTRIBUTES | SEE ALSO

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