Crontab, at и т.д. Как выполнить файл в терминале?

./hello

at now + 3 minutes <<<'/home/username/Desktop/project/chess'

at now + 3 minutes <<<'x-terminal-emulator -e  "/home/mskopin/Desktop/chess"'

at now <<<"gnome-terminal -e /home/mskopin/Desktop/project_gmar/user_mode/server_tcp_threads"

gnome-terminal -e 'bash -c "/home/mskopin/Desktop/chess; exec bash"'

$ at now

at now <<<'/home/mskopin/Desktop/project_gmar/user_mode/server_tcp_threads'

#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <pthread.h>
#include <string.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <netdb.h>
 
#define MAX_CONNENTIONS 5
 
void* create_listening_server(void* arg);
void accept_connections(int sockin, struct addrinfo *servinfo);
 
void* receive_from_remote_host(void* arg);
 
typedef struct _addr{
    char ip[50];
    char port[10];
} ADDRESS;
pthread_t th1, th3;
 
int main(void)
{
 
    ADDRESS addr;
    int res = -1;
//
    //printf("\nEnter IP address to communicate to: ");
    //fgets(addr.ip, 50, stdin);
    strcpy(addr.ip,"10.0.0.10");
    //addr.ip[strlen(addr.ip) - 1] = '\0';
//
    //printf("Enter port number: ");
    //fgets(addr.port, 10, stdin);
    strcpy(addr.port,"5000");
    //addr.port[strlen(addr.port) - 1] = '\0';
//
    res = pthread_create(&th1, NULL, &create_listening_server, &addr);
    if(res != 0)
        perror("shr: thread create error");
 
    pthread_join(th1,NULL);
//
    printf("main() reporting that all threads have terminated\n");
 
    return EXIT_SUCCESS;
}
 
//----------------- Начало сервера по протоколу TCP ------------------
 
void* create_listening_server(void* arg)
{
// server
    ADDRESS addr = *((ADDRESS*) arg);
    int sockin, sockin_connected;
    struct addrinfo hints, *servinfo;
    struct sockaddr_in client_addr;
    int mytrue = 1, res = -1;
//
    printf("\nserver: IP = %s port = %s\n", addr.ip, addr.port);
    memset(&hints, 0, sizeof hints);
    hints.ai_family   = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_flags    = AI_PASSIVE; // use my IP address
//
    if ((getaddrinfo(NULL, addr.port, &hints, &servinfo)) != 0){
        perror("error getaddrinfo");
        exit(1);
    }
// --------------------------------------------------------------------
    sockin = socket(servinfo->ai_family, servinfo->ai_socktype, 0 );
    if(-1 == sockin){
        perror("shr: error on server socket create");
        pthread_exit(0);
    }
//set the socket options: 
    if (setsockopt(sockin, SOL_SOCKET, SO_REUSEADDR, &mytrue, sizeof(int)) < 0){
         perror("Setsockopt");
         exit(1);
    }
    if (setsockopt(sockin, SOL_SOCKET, 15/*SO_REUSEPORT*/, (const char*)&mytrue, sizeof(mytrue)) < 0) {
        perror("setsockopt(SO_REUSEPORT) failed");
    }
 
    if(-1 == bind(sockin, servinfo->ai_addr, servinfo->ai_addrlen) ){
        perror("shr: error on bind");
        pthread_exit(0);
    }
 
    if (listen(sockin, MAX_CONNENTIONS) == -1){
        perror("shr: error on listen");
        pthread_exit(0);
    }
 
    printf("\nTCPServer: Waiting for client on port %s...\n", addr.port);
    fflush(stdout);
//  
    accept_connections(sockin, servinfo);
    return NULL;
}
 
void accept_connections(int sockin, struct addrinfo *servinfo)
{
    printf("HERE1");
    do{
        struct sockaddr_in client_addr;
        int sockin_connected, res = -1;
 
        sockin_connected = accept(sockin, servinfo->ai_addr, &servinfo->ai_addrlen);
        printf("\n2-socket %d\n", sockin);
        printf("\n3-connected_sock %d\n", sockin_connected);
 
        client_addr = *((struct sockaddr_in *)servinfo->ai_addr);
    
        printf("\nReceived a connection from %s , port %d",inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
 
        res = pthread_create(&th3, NULL, &receive_from_remote_host, &sockin_connected);
        if(res != 0) perror("shr: thread create error");
        sleep(1);
    }while( pthread_join(th3,NULL) );
 
    freeaddrinfo(servinfo);
    close(sockin);
}
 
void* receive_from_remote_host(void* arg)
{
 
    int received_bytes;
    char buf[1024];
    char newbuf[1024];
    int sockin_connected = *((int*)arg);
    printf("\nclient: sockin_connected %d\n", sockin_connected);
    // receive data from remote client:
    do{
        memset(buf, 0, sizeof(buf));
        received_bytes = recv(sockin_connected, buf, 1024, 0);
//
        if(0 == strlen(buf)) continue;
        printf("\nreceived message: %s " , buf);
        fflush(stdout);
        sleep(1);
        if( (strcmp(buf,"Alarm"))==0 ){
            strcpy(buf,"q\n");
            system("gnome-terminal -e "bash -c \'echo Alarm Alarm; exec bash \'""); // Команда, которая не работает!!!
        }
        send(sockin_connected, buf, strlen(buf), 0);
    }while((strcmp(buf , "q\n") != 0 && strcmp(buf , "Q\n") != 0));
    close(sockin_connected);
 
    return NULL;
}
//---------------- Конец сервера --------------------------