Color text in terminal applications in UNIX

CUnixTerminal

C Problem Overview


I started to write a terminal text editor, something like the first text editors for UNIX, such as vi. My only goal is to have a good time, but I want to be able to show text in color, so I can have syntax highlighting for editing source code.

How can I achieve this? Is there some special POSIX API for this, or do I have to use ncurses? (I'd rather not)

Any advice? Maybe some textbooks on the UNIX API?

C Solutions


Solution 1 - C

This is a little C program that illustrates how you could use color codes:

#include <stdio.h>

#define KNRM  "\x1B[0m"
#define KRED  "\x1B[31m"
#define KGRN  "\x1B[32m"
#define KYEL  "\x1B[33m"
#define KBLU  "\x1B[34m"
#define KMAG  "\x1B[35m"
#define KCYN  "\x1B[36m"
#define KWHT  "\x1B[37m"

int main()
{
    printf("%sred\n", KRED);
    printf("%sgreen\n", KGRN);
    printf("%syellow\n", KYEL);
    printf("%sblue\n", KBLU);
    printf("%smagenta\n", KMAG);
    printf("%scyan\n", KCYN);
    printf("%swhite\n", KWHT);
    printf("%snormal\n", KNRM);

    return 0;
}

Solution 2 - C

Different solution that I find more elegant

Here's another way to do it. Some people will prefer this as the code is a bit cleaner. There are no %s and a RESET color to end the coloration.

#include <stdio.h>

#define RED   "\x1B[31m"
#define GRN   "\x1B[32m"
#define YEL   "\x1B[33m"
#define BLU   "\x1B[34m"
#define MAG   "\x1B[35m"
#define CYN   "\x1B[36m"
#define WHT   "\x1B[37m"
#define RESET "\x1B[0m"

int main() {
  printf(RED "red\n"     RESET);
  printf(GRN "green\n"   RESET);
  printf(YEL "yellow\n"  RESET);
  printf(BLU "blue\n"    RESET);
  printf(MAG "magenta\n" RESET);
  printf(CYN "cyan\n"    RESET);
  printf(WHT "white\n"   RESET);

  return 0;
}

This program gives the following output:

enter image description here


Simple example with multiple colors

This way, it's easy to do something like:

printf("This is " RED "red" RESET " and this is " BLU "blue" RESET "\n");

This line produces the following output:

execution's output

Solution 3 - C

You probably want ANSI color codes. Most *nix terminals support them.

Solution 4 - C

Use ANSI escape sequences. This article goes into some detail about them. You can use them with printf as well.

Attributions

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionManganoView Question on Stackoverflow
Solution 1 - CkarlphillipView Answer on Stackoverflow
Solution 2 - CDavid GuyonView Answer on Stackoverflow
Solution 3 - CnmichaelsView Answer on Stackoverflow
Solution 4 - CVivin PaliathView Answer on Stackoverflow