putc(3S)               UNIX System V(C Development Set)                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)               UNIX System V(C Development Set)                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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