Linux C program, through the simplest pipe (' | ' ) To implement data transfer between two programs

The pipeline used in this article is the ' | ' in Linux that puts the output of the previous program into the last program's input. symbols, not the pipe of your own implementation

Code Listing 1: Program A.C output "HelloWorld", and the output is caught by B.C through the pipeline

A.C Code

#include <stdio.h>void main () {printf ("Hello world!:-P \ n");}

B.C Code

#include  <stdio.h>void main () {    char input[100];     char ch;    int i = 0;    while (ch =  getchar ())     {        if  (ch !=   ' \ n ')         {             input[i++] = ch;        }         else        {             input[i] =  ';     '         break;        }     }    printf (":-)  %s\n",  input);}

Compile and run, enter the command:

GCC a.c-o agcc b.c-o b./a |./b

Run effect

Code Listing 2: Program A.C input color as parameter, pass to B.C, output "Hello world!" of specified color

A.C Code

#include <stdio.h> #include <stdlib.h>void main (int argc, char *argv[]) {//Output main function received parameter int i;    for (i = 1; i < argc; i++) {printf ("%s\n", Argv[i]);    } printf ("end\n"); Exit (exit_success);}

B.C Code

#include  <stdio.h> #include  <stdlib.h> #include  <string.h>void main () {     char s[20];    while  (1)     {  &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;SCANF ("%s",  s);         if  (strcmp (s,  "Black")  == 0)         {             printf ("\e[30;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if   (strcmp (s,  "red")  == 0)         {             printf ("\e[31;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if  (strcmp (s,  "green")  == 0)         {             printf ("\e[32;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if   (strcmp (s,  "yellow")  == 0)         {             printf ("\e[33;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if   (strcmp (s,  "Blue")  == 0)         {             printf ("\e[34;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if  (strcmp (s,  "purple")  == 0)          {            printf ("\e[35;40;1m%s\e[37;40;0 M\n ", " hello world! ");         }        else if   (strcmp (s,  "Darkgreen")  == 0)         {             printf ("\e[36;40;1m%s\e[37;40;0m\n",  " Hello world! ");         }        else if   (strcmp (s,  "white")  == 0)         {             printf ("\e[37;40;1m%s\e[37;40;0m\n",  "Hello  world! ");         }        else if  (strcmp (s,  "End")  != 0)          {            printf ("Hello  World!  (Unknown color) \ n ");        }         else        {             printf ("end!\n");             break;        }    }     exit (exit_success);}

Compile and run, enter the command:

GCC a.c-o agcc b.c-o b./a parameters |./b

Run effect

END

Linux C program, through the simplest pipe (' | ' ) To implement data transfer between two programs