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Sunday, May 23, 2021

Fedora 33 : Programming with the ncurses library - part 001.

I started learning C and C ++ many years ago. Around 2004, the virtualization and S.D.K. class system for the Windows operating system confused me and was not to my advantage. Later I realized that it is more advantageous and faster to create your own tools with other programming languages. It turned out that I'm right and today I'm going to show you how simple it is to use C programming on the Linux Fedora 33 distro.
This library is easy to install on the Fedora Linux distro:
[root@desk mythcat]# dnf install ncurses-devel
Last metadata expiration check: 2:33:29 ago on Sun 23 May 2021 07:15:17 PM EEST.
Package ncurses-devel-6.2-3.20200222.fc33.x86_64 is already installed.
Package ncurses-devel-6.2-3.20200222.fc33.i686 is already installed.
Dependencies resolved.
Nothing to do.
Complete!
I created a folder and with the vim editor, I created my file called test_001.c for the first test.
[mythcat@desk ~]$ mkdir ncursesProject
[mythcat@desk ~]$ cd ncursesProject/
[mythcat@desk ncursesProject]$ vim test_001.c
This is the content to initiate and display a simple text with this library:
#include <ncurses.h>
 
int main(void){ 
        initscr();                      /* start curses mode */
        printw("Hello World !");        /* print Hello World */
        refresh();                      /* send to the real screen */
        getch();                        /* wait for user input */
        endwin();                       /* end curses mode */
        return 0;
} 
I used cc and gcc commands for C compilers to test this example and it works great:
[mythcat@desk ncursesProject]$ cc -o test_001 test_001.c -lncurses
[mythcat@desk ncursesProject]$ ls -l
total 32
-rwxr-xr-x 1 mythcat mythcat 25312 May 23 22:14 test_001
-rw-r--r-- 1 mythcat mythcat   386 May 23 22:14 test_001.c
[mythcat@desk ncursesProject]$ ./test_001 
[mythcat@desk ncursesProject]$ gcc -o test_001_gcc test_001.c -lncurses
[mythcat@desk ncursesProject]$ ./test_001_gcc 
#include <ncurses.h>

int main() { 
    // create the pointer to the window
    WINDOW *w;
    // define the data
    char list[4][8] = { "","Festila", "George", "Catalin"};
    char item[8];
    int ch, i = 0, width = 8;
    initscr(); // initialize Ncurses
    // create the new window with ncurses
    w = newwin( 6, 11, 0, 0 ); 
    box( w, 0, 0 ); // sets default borders for the window
    // now print all the menu items and highlight the first one
    for(i=0; i<4; i++) 
        {
        if( i != 0 ) 
            // highlights the first item.
            wattron( w, A_STANDOUT ); 
        else
            // highlights the next item.
            wattroff( w, A_STANDOUT );
            sprintf(item, "%-8s",  list[i]);
            mvwprintw( w, i+1, 2, "%s", item );
            //wrefresh( w );
        }
        wrefresh( w ); // update the terminal screen
        i = 0;
        noecho(); // disable echoing of characters on the screen
        keypad( w, TRUE ); // enable keyboard input for the window.
        curs_set(0); // hide the default screen cursor.
        
    // get the input if is not q key presed then run
    while(( ch = wgetch(w)) != 'q')
    { 
        // right pad with spaces to make the items appear with even width.
        sprintf(item, "%-8s",  list[i]); 
        mvwprintw( w, i+1, 2, "%s", item ); 

        // use a variable to increment or decrement the value based on the input.
        switch( ch ) 
        {
            case KEY_UP:
            i--; // increment 
            // stop the number of count list items -1
            i = ( i<0 ) ? 3 : i;
            break;
            case KEY_DOWN:
            i++; // increment
            // stop the number of count list items 
            i = ( i>2 ) ? 3 : i;
            break;
        }
    
        // now highlight the next item in the list.
        wattron( w, A_STANDOUT );
        sprintf(item, "%-8s",  list[i]);
        mvwprintw( w, i+1, 2, "%s", item);
        wattroff( w, A_STANDOUT );
    }
    // delete window
    delwin( w );
    // stop the window
    endwin();
}
This is the result:

Fedora 33 : Wordpress application desktop by Automattic tested on linux.

This application come for Android , Desktop and Mobile.
You can see this application on this website.
This is an screenshot with the application run it on Fedora Linux distro:
Download it unarchive and used like this:
[mythcat@desk ~]$ cd wordpress.com-linux-x64-6.14.0/
[mythcat@desk wordpress.com-linux-x64-6.14.0]$ ls -la
total 176264
drwxrwxrwx    5 mythcat mythcat      4096 Apr 30 14:23 .
drwx------. 104 mythcat mythcat     12288 May 23 12:29 ..
-rwxrwxrwx    1 mythcat mythcat    124662 Apr 30 14:23 chrome_100_percent.pak
-rwxrwxrwx    1 mythcat mythcat    187289 Apr 30 14:23 chrome_200_percent.pak
-rwxrwxrwx    1 mythcat mythcat   4743960 Apr 30 14:23 chrome-sandbox
-rwxrwxrwx    1 mythcat mythcat  10527632 Apr 30 14:23 icudtl.dat
-rwxrwxrwx    1 mythcat mythcat    249240 Apr 30 14:23 libEGL.so
-rwxrwxrwx    1 mythcat mythcat   3064616 Apr 30 14:23 libffmpeg.so
-rwxrwxrwx    1 mythcat mythcat   6990656 Apr 30 14:23 libGLESv2.so
-rwxrwxrwx    1 mythcat mythcat   3908248 Apr 30 14:23 libvk_swiftshader.so
-rwxrwxrwx    1 mythcat mythcat   6710080 Apr 30 14:23 libvulkan.so
-rwxrwxrwx    1 mythcat mythcat      1060 Apr 30 14:23 LICENSE.electron.txt
-rwxrwxrwx    1 mythcat mythcat   4562357 Apr 30 14:23 LICENSES.chromium.html
drwxrwxrwx    2 mythcat mythcat      4096 Apr 30 14:23 locales
drwxrwxrwx    3 mythcat mythcat        17 Apr 30 14:23 resources
-rwxrwxrwx    1 mythcat mythcat   5035565 Apr 30 14:23 resources.pak
-rwxrwxrwx    1 mythcat mythcat     51449 Apr 30 14:23 snapshot_blob.bin
drwxrwxrwx    2 mythcat mythcat        43 Apr 30 14:23 swiftshader
-rwxrwxrwx    1 mythcat mythcat    172276 Apr 30 14:23 v8_context_snapshot.bin
-rwxrwxrwx    1 mythcat mythcat       107 Apr 30 14:23 vk_swiftshader_icd.json
-rwxrwxrwx    1 mythcat mythcat 134100640 Apr 30 14:23 wpcom
[mythcat@desk wordpress.com-linux-x64-6.14.0]$ ./wpcom 
{"name":"calypso","hostname":"desk","pid":9931,"reqId":"066e63b4-d04c-4210-af52-6419e4a156fb","level":30,
"method":"GET","status":200,"length":"12940","url":"/post/null","duration":66.718,
"httpVersion":"1.1","env":"desktop","userAgent":"Chrome 87","rawUserAgent":"Mozilla/5.0 (X11; Linux x86_64)
AppleWebKit/537.36 (KHTML, like Gecko) WordPressDesktop/6.14.0 Chrome/87.0.4280.67 Electron/11.0.4 
Safari/537.36","remoteAddr":"127.0.0.1","msg":"request finished","time":"2021-05-23T09:48:44.683Z","v":0}
{"name":"calypso","hostname":"desk","pid":9931,"reqId":"6da5223a-07e0-4202-8ab0-e28940a54fbc","level":30, ...
I send my issue on GitHub for this application.
... more information on the official blog ...