@c ----------------------------------------------------------------------
@node putc, stdio
@heading @code{putc}
@subheading Syntax

@example
#include <stdio.h>

int putc(int c, FILE *file);
@end example

@subheading Description

This function writes one character to the given @var{file}.

@subheading Return Value

The character written.

@subheading Example

@example
while ((c=getc(stdin)) != EOF)
  putc(c, stdout);
@end example

@c ----------------------------------------------------------------------
@node putchar, stdio
@heading @code{putchar}
@subheading Syntax

@example
#include <stdio.h>

int putchar(int c);
@end example

@subheading Description

This is the same as @code{fputc(c, stdout)}.  @xref{fputc}

@subheading Return Value

The character written.

@subheading Example

@example
while ((c = getchar()) != EOF)
  putchar(c);
@end example

@c ----------------------------------------------------------------------
@node putenv, environment
@heading @code{putenv}
@subheading Syntax

@example
#include <stdlib.h>

int putenv(const char *env);
@end example

@subheading Description

This function adds an entry to the program's environment.  The string
passed must be of the form @code{NAME}=@code{VALUE}.  Any existing value
for the environment variable is gone. 

Note that the string passed to @code{putenv} becomes part of the
environment itself, so you must not free it. 

@subheading Return Value

Zero on success, nonzero on failure.

@subheading Example

@example
putenv("SHELL=ksh.exe");
@end example

@c ----------------------------------------------------------------------
@node puts, stdio
@heading @code{puts}
@subheading Syntax

@example
#include <stdio.h>

int puts(const char *string);
@end example

@subheading Description

This function writes @var{string} to @code{stdout}, and then writes a
newline character. 

@subheading Return Value

Nonnegative for success, or @code{EOF} on error.

@subheading Example

@example
puts("Hello, there");
@end example

@c ----------------------------------------------------------------------
@node putw, stdio
@heading @code{putw}
@subheading Syntax

@example
#include <stdio.h>

int putw(int x, FILE *file);
@end example

@subheading Description

Writes a single binary word in native format to @var{file}.

@subheading Return Value

The value written, or @code{EOF} for end-of-file or error.  Since
@code{EOF} is a valid integer, you should use @code{feof} or
@code{ferror} to detect this situation. 

@subheading Example

@example
putw(12, stdout);
@end example

