Embedded Linux multi-process programming

Embedded Linux multi-process programming

The main program displays a text menu that provides the following services, requiring each service to be provided by generating child processes.
Services include: Calendar information display, date information display, Judgment Leap year service, file copy function, digital sorting function, Exit function.

Code and documentation (with flowchart): http://download.csdn.net/download/jingjingxujiayou/7540893

#include <stdio.h> #include <sys/types.h> #include <unistd.h> #include <time.h> #include < fcntl.h> #include <sys/stat.h>void displaycalen ();//1 Show calendar void Displaydate (); 2 Display date void Leapyear ();//3 judgment Leap Year void CopyFile ();//4 file assignment function void Sortnum (); 5 to number sort int start ();//Start Interface void menu ();    menu function int Start () {int n;    printf ("-----Linux multi-process programming-----\ n");    printf ("Display of the 1st calendar information \ n");    printf ("Display of information for the period 2nd \ n");    printf ("3 Judgment leap Year information service \ n");    printf ("Assignment function for 4 files \ n");    printf ("5 numbers sorted \ n");    printf ("6 exit program \ n");    printf ("Please input your choose (1-6)");    scanf ("%d", &n); return n;} void Displaycalen () {EXECLP ("cal", "Cal", "-sy", (char *) 0);}    2 Displays the current system date void Displaydate () {struct TM *ptr;    time_t it;    It=time (NULL);    Ptr=localtime (&it); printf ("%4d%02d month%02d day%d:%d:%d\n", ptr->tm_year+1900,ptr->tm_mon+1,ptr->tm_mday,ptr->tm_hour,ptr- &GT;TM_MIN,PTR-&GT;TM_SEC);}    3 judgement leap Year void Leapyear () {int m; printf ("Please input your yeaRS ");    scanf ("%d", &m); if (((0==m%4) && (0!=m%100)) | | (0==m%400))    {printf ("%d is a leap year \ n", m);    }else{printf ("%d is not a leap year \ n", m);    }}//4 Copy file void CopyFile () {const char* pathfile = "file1.c";    int In,out,flag;    Char buffer[1024];    in = Open ("file2.c", O_rdonly, S_IRUSR);    if ( -1 = = in) {printf ("Open file file2.c error!\n");    Return    } out = creat (PATHFILE,S_IWUSR);    if ( -1 = = out) {printf ("Create file%s error!\n", pathfile);    Return    } while ((flag = Read (in,buffer,1024)) >0) {write (Out,buffer,flag);    } close (in);    Close (out); printf ("Copy file file2.c to%s\n", pathfile);}        5 Sort the numbers void Sortnum () {int b[10]={29,59,8,9,16,7,2,98,29,10};    int i,j,t,k;    printf ("10 numbers in the array: \ n");    for (i = 0; i <; i + +) {printf ("%d\t", B[i]);    } printf ("\ n");                for (i=0;i<10-1;i++) for (k=i,j=i+1;j<10;j++) {if (B[k]<b[j]) {     K=j;       } if (i!=k) {t=b[i];                B[I]=B[K];            b[k]=t;    }} printf ("From large to small in order; \ n");    for (i=0;i<10;i++) printf ("%d\t", B[i]); printf ("\ n");}    void menu () {int choose, k=1;    pid_t child;    while (1) {Choose=start ();            Switch (choose) {Case 1:if ((Child=fork ()) ==-1) {printf ("error......\n");            }else if (child==0) {Displaycalen ();  }else if (Child > 0) {waitpid (child, NULL, 0);        } break;            Case 2:if ((Child=fork ()) ==-1) {printf ("error......\n");            }else if (child==0) {displaydate ();  }else if (Child > 0) {waitpid (child, NULL, 0);        } break;            Case 3:if ((Child=fork ()) ==-1) {printf ("error......\n");   }else if (child==0) {             Leapyear ();  }else if (Child > 0) {waitpid (child, NULL, 0);        } break;            Case 4:if ((Child=fork ()) ==-1) {printf ("error......\n");            }else if (child>0) {CopyFile ();  }else if (child = = 0) {waitpid (child, NULL, 0);        } break;            Case 5:if ((Child=fork ()) ==-1) {printf ("error......\n");            }else if (child==0) {sortnum ();  }else if (Child > 0) {waitpid (child, NULL, 0);        } break;            Case 6:system ("exit");        Break       Default:break;    }}}int Main () {menu (); return 0;}