putc(3S)            (C Programming Language Utilities)             putc(3S)


   NAME
         putc, putchar, fputc, putw - put character or word on a stream

   SYNOPSIS
         #include <stdio.h>

         int putc (int c, FILE *stream);

         int putchar (int c);

         int fputc (int c, FILE *stream);

         int putw (int w, FILE *stream);

   DESCRIPTION
         putc writes c (converted to an unsigned char) onto the output stream
         [see intro(3)] at the position where the file pointer (if defined) is
         pointing, and advances the file pointer appropriately.  If the file
         cannot support positioning requests, or stream was opened with append
         mode, the character is appended to the output stream.  putchar(c) is
         defined as putc(c, stdout).  putc and putchar are macros.

         fputc behaves like putc, but is a function rather than a macro.
         fputc runs more slowly than putc, but it takes less space per
         invocation and its name can be passed as an argument to a function.

         putw writes the word (i.e., integer) w to the output stream (where
         the file pointer, if defined, is pointing).  The size of a word is
         the size of an integer and varies from machine to machine.  putw
         neither assumes nor causes special alignment in the file.

   SEE ALSO
         exit(2), lseek(2), write(2), abort(3C), fclose(3S), ferror(3S),
         fopen(3S), fread(3S), printf(3S), puts(3S), setbuf(3S), stdio(3S).

   DIAGNOSTICS
         On success, these functions (with the exception of putw) each return
         the value they have written.  putw returns ferror (stream).  On
         failure, they return the constant EOF.  This result will occur, for
         example, if the file stream is not open for writing or if the output
         file cannot grow.

   NOTES
         Because it is implemented as a macro, putc evaluates a stream
         argument more than once.  In particular, putc(c, *f++); doesn't work
         sensibly.  fputc should be used instead.

         Because of possible differences in word length and byte ordering,
         files written using putw are machine-dependent, and may not be read
         using getw on a different processor.



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   putc(3S)            (C Programming Language Utilities)             putc(3S)


         Functions exist for all the above defined macros.  To get the
         function form, the macro name must be undefined (e.g., #undef putc).



















































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