Watcom C Library : putc, putch, putchar, putenv, _putimage, _putimage_w, puts

 

 

Watcom C Library Reference : putc, putch, putchar, putenv, _putimage, _putimage_w, puts

 

 

 

 

putc

 

Synopsis : #include <stdio.h> 

              int putc( int c, FILE *fp );

 

Description : The putc function is equivalent to fputc, except it may be implemented as a macro. The putc function writes the character specified by the argument c to the output stream designated by fp.

 

 

Returns : The putc function returns the character written. If a write error occurs, the error indicator is set and putc returns EOF. When an error has occurred, errno contains a value indicating the type of error that has been detected.

 

 

See Also : fopen, fputc, fputchar, fputs, putchar, puts, ferror

 

Example :

#include <stdio.h>

void main( )

{
    FILE   *fp;

    int     c;

    fp = fopen( "file", "r" );

    if ( fp != NULL ) {

        while( (c = fgetc( fp )) != EOF )
            putc( c, stdout );

        fclose( fp );

    }

}

 

Classification : ANSI
Systems : All

 

 

 

 

 

 

putch

 

Synopsis : #include <conio.h> 

              int putch( int c );

 

Description : The putch function writes the character specified by the argument c to the console.

 

 

Returns : The putch function returns the character written.

 

 

See Also : getch, getche, kbhit, ungetch

 

Example :

#include <conio.h> 

#include <stdio.h>

void main( )

{
    FILE    *fp;

    int     c;

    fp = fopen( "file", "r" );

    if ( fp != NULL ) {

        while( (c = fgetc( fp )) != EOF )
            putch ( c );

    }
    fclose( fp );

}

 

Classification : WATCOM
Systems : All

 

 

 

 

 

 

putchar

 

Synopsis : #include <stdio.h> 

              int putchar( int c );

 

Description : The putchar function writes the character specified by the argument c to the output stream stdout.

The function is equivalent to fputc( c, stdout );

 

Returns : The putchar function returns the character written. If a write error occurs, the error indicator is set and putchar returns EOF. When an error has occurred, errno contains a value indicating the type of error that has been detected.

 

 

See Also : fputc, fputchar, fputs, putc

 

Example :

#include <stdio.h>

void main( )

{
    FILE    *fp;

    int     c;

    fp = fopen( "file", "r" );

    c = fgetc( fp );

    while( c != EOF ) {
        putchar( c );

        c = fgetc( fp );

    }
    fclose( fp );

}

 

Classification : ANSI
Systems : All

 

 

 

 

 

 

putenv

 

Synopsis : #include <process.h> 

              int putenv( const char *env_name );

 

Description : The environment list consists of a number of environment names, each of which has a value associated with it. Entries can be added to the environment list with the DOS set command or with the putenv function.

 

All entries in the environment list can be displayed by using the DOS set command with no arguments. A program can obtain the value for an environment variable by using the getenv function.

 

When the value of env_name has the format
    env_name=value

an environment name and its value is added to the environment list. When the value of env_name has the format
    env_name=

the environment name and value is removed from the environment list.

The matching is case-insensitive; all lowercase letters are treated as if they were in upper case.

The space into which environment names and their values are placed is limited. Consequently, the putenv function can fail when there is insufficient space remaining to store an additional value.

 

NOTE : If the argument env_name is not a literal string, you should duplicate the string, since putenv does not copy the value; for example,
    putenv( strdup( buffer ) );

To assign a string to a variable and place it in the environment list:
    C>SET INCLUDE=C:\WATCOM\H

To see what variables are in the environment list, and their current assignments:
    C>SET

    COMSPEC=C:\COMMAND.COM

    PATH=C:\;C:\WATCOM

    INCLUDE=C:\WATCOM\H
    C>

Returns : The putenv function returns zero when it is successfully executed and returns - 1 when it fails.

 

 

Errors : When an error has occurred, errno contains a value indicating the type of error that has been detected.

    ENOMEM     Not enough memory to allocate a new environment string.

 

 

See Also : clearenv, getenv, setenv

 

Example :

The following gets the string currently assigned to INCLUDE and displays it, assigns a new value to it, gets and displays it, and then removes the environment name and value.

#include <stdio.h> 

#include <stdlib.h>

void main( )

{
    char     *path;

    path = getenv ( "INCLUDE" );

 

    if ( path != NULL )
        printf( "INCLUDE=%s\n", path );

 

    if( putenv ( "INCLUDE=mylib;yourlib" ) != 0 )
        printf( "putenv failed" );

 

    path = getenv( "INCLUDE" );

    if ( path != NULL )
        printf( "INCLUDE=%s\n", path );

 

    if( putenv( "INCLUDE=" ) != 0 )
        printf( "putenv failed" );

}

 

produces the following :
INCLUDE=C:\WATCOM\H 

INCLUDE=mylib;yourlib

 

Classification : WATCOM
Systems : All

 

 

 

 

 

 

_putimage, _putimage_w

 

Synopsis : #include <graph.h> 

              void FAR putimage( short x, short y, char _HUGE *image, short mode );
              void FAR putimage_w( double x, double y, char _HUGE *image, short mode );


Description : The _putimage functions display the screen image indicated by the argument image. The _putimage function uses the view coordinate system. The _putimage_w function uses the window coordinate system.

The image is displayed upon the screen with its top left corner located at the point with coordinates (x, y). The image was previously saved using the _getimage functions. The image is displayed in a rectangle whose size is the size of the rectangular image saved by the _getimage functions.

The image can be displayed in a number of ways, depending upon the value of the mode argument. This argument can have the following values:

Values	Meaning
_GPSET	replace the rectangle on the screen by the saved image
_GPRESET	replace the rectangle on the screen with the pixel values of the saved image inverted; this produces a negative image
_GAND	produce a new image on the screen by ANDing together the pixel values from the screen with those from the saved image
_GOR	produce a new image on the screen by ORing together the pixel values from the screen with those from the saved image
_GXOR	produce a new image on the screen by exclusive ORing together the pixel values from the screen with those from the saved image: the original screen is restored by two successive calls to the _putimage function with this value, providing an efficient method to produce animated effects

 

 

Returns : The _putimage functions do not return a value.

 

 

See Also : _getimage, _imagesize

Example :

#include <conio.h> 

#include <graph.h> 

#include <malloc.h>

main( )

{
    char    *buf;

    int      y;

    _setvideomode( _VRES16COLOR );

    _ellipse( _GFILLINTERIOR, 100, 100, 200, 200 );

    buf = malloc( _imagesize( 100, 100, 201, 201 ) );

 

    if( buf != NULL ) {
        _getimage( 100, 100, 201, 201, buf );

        _putimage( 260, 200, buf, _GPSET );

        _putimage( 420, 100, buf, _GPSET );

        for( y = 100; y < 300; ) {
            _putimage( 420, y, buf, _GXOR );

            y += 20;

            _putimage( 420, y, buf, _GXOR );

        }
        free( buf );

    }

    getch( );

    _setvideomode( _DEFAULTMODE );

}

 

Classification : PC Graphics
Systems : _putimage - DOS, QNX 

             _putimage_w - DOS, QNX

 

 

 

 

 

 

 

puts

 

Synopsis : #include <stdio.h> 

              int puts( const char *buf );


Description : The puts function writes the character string pointed to by buf to the output stream
designated by stdout, and appends a new-line character to the output. The terminating null character is not written.

 

 

Returns : The puts function returns a non-zero value if an error occurs; otherwise, it returns zero. When an error has occurred, errno contains a value indicating the type of error that has been detected

 

 

See Also : fputs, putc

 

Example :

#include <stdio.h>

void main( )

{
    FILE     *fp;

    char     buffer[80];

    fp = freopen( "file", "r", stdin );

    while( gets ( buffer ) != NULL ) {
        puts ( buffer );
    }
    fclose( fp );

}

 

Classification : ANSI
Systems : All

 

 

 

 

 

 

 

 

This manual describes the WATCOM C library for DOS, Windows, and OS/2, It includes the Standard C Library (as defined in the ANSI C Standard).

 

WATCOM C Language Reference manual describes the ANSI C Programming language and extensions to it which are supported by WATCOM C/C++ (32bit)