1fwrite(3C)               Standard C Library Functions               fwrite(3C)
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NAME

6       fwrite - binary output
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SYNOPSIS

9       #include <stdio.h>
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11       size_t fwrite(const void *ptr, size_t size, size_t nitems, FILE *stream);
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DESCRIPTION

15       The  fwrite()  function writes, from the array pointed to by ptr, up to
16       nitems elements whose size is specified by size, to the stream  pointed
17       to  by  stream.  For  each object, size calls are made to the fputc(3C)
18       function, taking the values (in order) from an array of  unsigned  char
19       exactly  overlaying  the  object.  The  file-position indicator for the
20       stream (if defined) is advanced by the  number  of  bytes  successfully
21       written.  If  an error occurs, the resulting value of the file-position
22       indicator for the stream is unspecified.
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25       The st_ctime and st_mtime fields of the file will be marked for  update
26       between  the  successful  execution of fwrite() and the next successful
27       completion of a call to fflush(3C) or fclose(3C) on the same stream  or
28       a call to exit(2) or abort(3C).
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RETURN VALUES

31       The fwrite() function returns the number of elements successfully writ‐
32       ten, which might be less than nitems if a write error  is  encountered.
33       If  size or nitems is 0, fwrite() returns 0 and the state of the stream
34       remains unchanged. Otherwise, if a write error occurs, the error  indi‐
35       cator for the stream is set and errno is set to indicate the error.
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ERRORS

38       Refer to fputc(3C).
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USAGE

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

47       See attributes(5) for descriptions of the following attributes:
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52       ┌─────────────────────────────┬─────────────────────────────┐
53       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
54       ├─────────────────────────────┼─────────────────────────────┤
55       │Interface Stability          │Standard                     │
56       ├─────────────────────────────┼─────────────────────────────┤
57       │MT-Level                     │MT-Safe                      │
58       └─────────────────────────────┴─────────────────────────────┘
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SEE ALSO

61       write(2),  fclose(3C),  ferror(3C),  fopen(3C),  fread(3C),   getc(3C),
62       gets(3C), printf(3C), putc(3C), puts(3C), attributes(5), standards(5)
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66SunOS 5.11                        24 Jul 2002                       fwrite(3C)
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