Using sed with the execvp to cut part of stout. C - c

Question

I'm using a function that echo a string and redirect output to a sed input in c.
If i echo a string like "hello: bye bye", i need to cut everything before the ":". So i buildt a function that fork and pipe for this but sed won't recognize my regex:
void sender (char * str_ ,char * pipe_ ,char **args_) {
int fd[2];
int pid;
char* cmd1[] = {"echo", str_,NULL};
char* sed[] = {"sed","'[^:]*$'",NULL};
int status;
pid = fork();
if (pid == 0) {
if(pipe(fd) < 0){
exit(100);
}
pid = fork();
if (pid == 0) {
close(fd[0]);
dup2(fd[1], 1);
close(fd[1]);
execvp(cmd1[0], cmd1);
printf("Error in execvp1\n");
}else{
close(fd[1]);
wait(&status);
dup2(fd[0],0);
close(fd[0]);
dup2(1,2);
execvp(sed[0],sed);
printf("Error in execvp2\n");
}
}
else{
close(fd[0]);
close(fd[1]);
wait(&status);
wait(&status);
}
}
The output is error for every line read because of sed:expression -e #1, character 1: unknown command: `''

Answer 1

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
void pipe_exec(int pfd[], char *cmd_args[], int redirect_output)
{
printf("%s, pid %d\n", cmd_args[0], getpid());
if (redirect_output)
dup2(pfd[1], 1);
else
dup2(pfd[0], 0);
close(pfd[0]);
close(pfd[1]);
execvp(cmd_args[0], cmd_args);
printf("Error in execvp\n");
exit(1);
}
void sender(char *str_, char *unused1, char **unused2)
{
int status, pid, fd[2];
char *cmd1[] = { "echo", str_, NULL };
char *sed[] = { "sed", "s/[^:]*://", NULL };
if (pipe(fd) < 0)
exit(100);
pid = fork();
if (pid == 0)
pipe_exec(fd, cmd1, 1);
pid = fork();
if (pid == 0)
pipe_exec(fd, sed, 0);
close(fd[0]);
close(fd[1]);
wait(&status);
wait(&status);
}
int
main(void)
{
sender("hello: bye bye", NULL, NULL);
return (0);
}