Linux下的C编程程序源代码

hobby! · 发表于 2004-11-22 10:46:25

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#define DATASIZE 10

typedef struct stringdata

{

char *string;

int iscontinuing;

struct stringdata *next;

} mydata;

mydata *append(mydata *start, char *input);

void displaydata(mydata *start);

void freedata(mydata *start);

int main(void)

{

char input[DATASIZE];

mydata *start=NULL;

printf("ENTER SOME DATA,AND PRESS Ctrl+D WHEN DONE. \n");

while(fgets(input, sizeof(input), stdin))

{

        start=append(start, input);

}

displaydata(start);

freedata(start);

return 0;

}

mydata *append(mydata *start, char *input)

{

   mydata *cur=start, *prev=NULL, *new;

while(cur)

{

        prev=cur;

        cur=cur->next;

}

cur=prev;

new=malloc(sizeof(mydata));

if(!new)

{

        printf("COULDN’T ALLOCATE MEMORY! \n");

        exit(255);

}

if(cur)

        cur->next=new;

else

        start=new;

cur=new;

if(!(cur->string=malloc(sizeof(input)+1)))

{

printf("ERROR ALLOCATING MEMORY! \n");

exit(255);

}

strcpy(cur->string, input);

cur->iscontinuing=!(input[strlen(input)-1]=='\n'||input[strlen(input)-1]=='\r');

cur->next=NULL;

return start;

}

void displaydata(mydata *start)

{

mydata *cur;

int linecounter=0, structcounter=0;

int newline=1;

cur=start;

while(cur)

{

if(newline)

        printf("LINE %d:",++linecounter);

structcounter++;

printf("%s",cur->string);

newline=!cur->iscontinuing;

cur=cur->next;

}

printf("THIS DATA CONTAINED %d LINES AND WAS STORED IN %d STRUCTS. \n",

linecounter,structcounter);

}

void freedata(mydata *start)

{

mydata *cur, *next=NULL;

cur=start;

while(cur)

{

        next=cur->next;

   free(cur->string);

        free(cur);

        cur=next;

}

}

hobby! · 发表于 2004-11-22 10:51:53

#include <stdio.h>

#include <string.h>

void upcase(char *inputstring, char *newstring);

int main(void)

{

char *string;

upcase("Hello",string);

printf("str1=%s \n", string);

capitao("Goodbye", string);

printf("str2=%s\n", string);

free(string);

return 0;

}

void upcase(char *inputstring, char *newstring)

{

int counter;

if(!newstring)

{

        if(!(newstring=realloc(NULL, strlen(inputstring)+1)))

{

        printf("ERROR ALLOCATING MEMORY! \n");

        exit(255);

}

}

else

{

        if(!(newstring=realloc(newstring, sizeof(inputstring)+1)))

        {

        printf("ERROR REALLOCATING MEMORY! \n");

        exit(255);

}

}

      strcpy(newstring, inputstring);

for(counter=0; counter<strlen(newstring); counter++)

{

        if(newstring[counter]>=97&&newstring[counter]<=122)

         newstring[counter]-=32;

}

return ;

}

hobby! · 发表于 2004-11-22 11:00:37

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/mman.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

int write_buffer(int fd, const void *buf, int count);

int outfile;

int main(void)

{

char *mapped;

char *ptr;

if(outfile=open("test.dat", O_RDWR|O_CREAT|O_TRUNC, 0640)==-1)

{

printf("COULDN'T OPEN THIS FILE!\n");

exit(254);

}

lseek(outfile,1000,SEEK_SET);

if(write(outfile,"\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

}

mapped=mmap(NULL, 1000, PROT_READ|PROT_WRITE,MAP_SHARED, outfile, 0);

if(!mapped)

printf("ERROR, MMAP FAILED!\n");

ptr=mapped;

printf("PLEASE ENTER A NUMBER:");

fgets(mapped, 80, stdin);

ptr=mapped;

sprintf(ptr,"YOUR NUMBER TIMES TWO IS:%d.\n",atoi(mapped)*2);

printf("YOUR NUMBER TIMES TWO IS:%d\n",atoi(mapped)*2);

msync(mapped, 1000, MS_SYNC);

munmap(mapped,1000);

if(!close(outfile))

{

printf("POSSIBLY SERIOUS ERROR,CLOSE FILE FAILED");

exit(254);

}

return 0;

}

int write_buffer(int fd, const void *buf, int count)

{

const void *pts=buf;

int status=0, n;

if(count<0)

return(-1);

while(status!=count)

{

        if(n=write(outfile, "\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

        }

        if(n<0)

            return(n);

        status+=n;

}

return(status);

}

hobby! · 发表于 2004-11-22 11:02:01

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/mman.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

int write_buffer(int fd, const void *buf, int count);

int main(void)

{

int outfile;

char *mapped;

char *ptr;

int count;

if(outfile=open("test.dat", O_RDWR|O_CREAT|O_TRUNC, 0640)==-1)

{

printf("COULDN’T OPEN THIS FILE!\n");

exit(254);

}

lseek(outfile, 1000, SEEK_SET);

if(write(outfile, "\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

}

mapped=mmap(NULL, 1000, PROT_READ|PROT_WRITE,MAP_SHARED, outfile, 0);

if(!mapped)

{

printf("ERROR, MMAP FAILED!\n");

exit(254);

}

for(count=0; count<1000; count++)

{

if(*(mapped+count)>=97&&*(mapped+count)<=122)

*(mapped+ count)-= 32;

}

msync(mapped, 1000, MS_SYNC);

munmap(mapped,1000);

if(!close(outfile))

{

printf("POSSIBLY SERIOUS ERROR,CLOSE FILE FAILED");

exit(254);

}

return 0;

}

hobby! · 发表于 2004-11-22 11:02:45

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

int main(void)

{

pid_t pid;

if((pid=fork())<0)

{

printf("fork error! \n");

exit(1);

}

else if(pid==0)

{

printf("Child process is printing.\n");

}

else

{

printf("Parent process is printing.\n");

}

exit(0);

}

hobby! · 发表于 2004-11-22 11:04:01

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

int main(void)

{

pid_t pid;

if((pid=vfork())<0)

{

printf("fork error! \n");

exit(1);

}

else if(pid==0)

{

printf("Child process is printing.\n");

}

else

{

printf("Parent process is printing.\n");

}

exit(0);

}

hobby! · 发表于 2004-11-22 11:04:46

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

int main(void)

{

pid_t pid;

if((pid=vfork())<0)

{

printf("fork error! \n");

exit(1);

}

else if(pid==0)

{

printf("Child process PID: %d.\n",getpid());

setenv("PS1", "CHILD\\$", 1);

printf("Process%4d: calling exec.\n",getpid());

if(execl("/bin/sh", "/bin/sh", "arg2", NULL)<0)

{

printf("Process%4d: execle error!\n",getpid());

exit(0);

}

printf("Process%4d: You should never see this because the child is already gone. \n",

getpid());

printf("Precess%4d: The child process is exiting.");

}

else

{

printf("Parent process PID:%4d.\n", getpid());

printf("Process%4d: The parent has fork process %d.\n", pid);

printf("Process%4d: The child has called exec or has exited.\n", getpid());

}

return 0;

}

hobby! · 发表于 2004-11-22 11:09:31

#include <sys/types.h>

#include <sys/wait.h>

#include <stdio.h>

void h_exit(int status);

int main(void)

{

pid_t pid;

int status;

if((pid=fork())<0)

{

        printf("fork error!\n");

        exit(0);

}

else if(pid==0)

        exit(7);

if(wait(&status)!=pid)

{

        printf("wait error!\n");

        exit(0);

}

h_exit(status);

if((pid=fork())<0)

{

        printf("fork error!\n");

        exit(0);

}

else if(pid==0)

        exit(1);

if(wait(&status)!=pid)

{

        printf("wait error!\n");

        exit(0);

}

h_exit(status);

if((pid=fork())<0)

{

        printf("fork error!\n");

        exit(0);

}

else if(pid==0)



if(wait(&status)!=pid)

{

        printf("wait error!\n");

        exit(0);

}

h_exit(status);

exit(0);

}

void h_exit(int status)

{

if(WIFEXITED(status))

        printf("normal termination, exit status=%d .\n", WEXITSTATUS(status));

else if(WIFSIGNALED(status))

        printf("abnormal termination, exit status=%d. \n", WTERMSIG(status));

}

hobby! · 发表于 2004-11-22 11:54:10

#include <sys/types.h>

#include <sys/wait.h>

#include <sys/resource.h>

#include <stdio.h>

#include <unistd.h>

#include <stdarg.h>

#include <unistd.h>

#include <stdlib.h>

void waitchildren(int signum);

void h_exit(int status);

int main(void)

{

pid_t pid;

int status;

if((pid=fork())<0)

{

        printf("fork error!\n");

        exit(0);

}

else if(pid==0)

{

        printf("Hello from the child process%4d!\n", getpid());

        setenv("PS1", "CHILD \ \ $", 1);

        printf("Process%4d: I’m calling exec. \n", getpid());

execl("/bin/sh", "/bin/sh", NULL);

printf("Process%4d: You should never see this because the child is already gone.\n", getpid());

}

else if(pid!=-1)

{

        printf("Hello from the parent process%4d!\n", getpid());

        printf("Process%4d: The parent has forked process %d. \n", getpid(),pid);

printf("Process%4d: The parent is waiting for the child to exit.\n", getpid());

wait4(pid, &status, 0, NULL);

h_exit(status);

}

return 0;

}

void h_exit(int status)

{

if(WIFEXITED(status))

        printf("normal termination, exit status=%d .\n", WEXITSTATUS(status));

else if(WIFSIGNALED(status))

        printf("abnormal termination, exit status=%d. \n", WTERMSIG(status));

}

hobby! · 发表于 2004-11-22 11:55:14

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

void forkerror(void);

void execerror(void);

int main(void)

{

pid_t pid;

if((pid=vfork())<0)

{

atexit(forkerror);

}

else if(pid==0)

{

printf("Child process PID: %d.\n",getpid());

setenv("PS1", "CHILD\\$", 1);

printf("Process%4d: calling exec.\n",getpid());

if(execl("/bin/sh", "/bin/sh", "arg2", NULL)<0)

{

atexit(execerror);

}

printf("Process%4d: You should never see this because the child is already gone. \n",

getpid());

printf("Precess%4d: The child process is exiting.");

}

else

{

printf("Parent process PID:%4d.\n", getpid());

printf("Process%4d: The parent has fork process %d.\n", pid);

printf("Process%4d: The child has called exec or has exited.\n", getpid());

}

return 0;

}

void forkerror(void)

{

printf("fork error!\n");

exit(1);

}

void execerror(void)

{

printf("exec error!\n");

exit(1);

}

hobby! · 发表于 2004-11-22 11:58:24

#include <sys/types.h>

#include <sys/wait.h>

#include <stdio.h>

void h_exit(int status);

static void forkerror(void);

static void waiterror(void);

int main(void)

{

pid_t pid;

int status;

if((pid=fork())<0)

{

        atexit(forkerror);

}

else if(pid==0)

        abort();

if(wait(&status)!=pid)

{

        atexit(waiterror);

}

h_exit(status);

exit(0);

}

void h_exit(int status)

{

if(WIFEXITED(status))

        printf("normal termination, exit status=%d .\n", WEXITSTATUS(status));

else if(WIFSIGNALED(status))

        printf("abnormal termination, exit status=%d. \n", WTERMSIG(status));

}

void forkerror(void)

{

printf("fork error!\n");

}

void waiterror(void)

{

printf("wait error!\n");

}

hobby! · 发表于 2004-11-22 12:07:25

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/mman.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

int write_buffer(int fd, const void *buf, int count);

int outfile;

int main(void)

{

char *mapped;

char *ptr;

if(outfile=open("test.dat", O_RDWR|O_CREAT|O_TRUNC, 0640)==-1)

{

printf("COULDN'T OPEN THIS FILE!\n");

exit(254);

}

lseek(outfile,1000,SEEK_SET);

if(write(outfile,"\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

}

mapped=mmap(NULL, 1000, PROT_READ|PROT_WRITE,MAP_SHARED, outfile, 0);

if(!mapped)

printf("ERROR, MMAP FAILED!\n");

ptr=mapped;

printf("PLEASE ENTER A NUMBER:");

fgets(mapped, 80, stdin);

ptr=mapped;

sprintf(ptr,"YOUR NUMBER TIMES TWO IS:%d.\n",atoi(mapped)*2);

printf("YOUR NUMBER TIMES TWO IS:%d\n",atoi(mapped)*2);

msync(mapped, 1000, MS_SYNC);

munmap(mapped,1000);

if(!close(outfile))

{

printf("POSSIBLY SERIOUS ERROR,CLOSE FILE FAILED");

exit(254);

}

return 0;

}

int write_buffer(int fd, const void *buf, int count)

{

const void *pts=buf;

int status=0, n;

if(count<0)

return(-1);

while(status!=count)

{

        if(n=write(outfile, "\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

        }

        if(n<0)

            return(n);

        status+=n;

}

return(status);

}

hobby! · 发表于 2004-11-22 12:07:49

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/mman.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

int write_buffer(int fd, const void *buf, int count);

int main(void)

{

int outfile;

char *mapped;

char *ptr;

int count;

if(outfile=open("test.dat", O_RDWR|O_CREAT|O_TRUNC, 0640)==-1)

{

printf("COULDN’T OPEN THIS FILE!\n");

exit(254);

}

lseek(outfile, 1000, SEEK_SET);

if(write(outfile, "\0",1)==-1)

{

printf("ERROR, WRITE FAILED!\n");

exit(254);

}

mapped=mmap(NULL, 1000, PROT_READ|PROT_WRITE,MAP_SHARED, outfile, 0);

if(!mapped)

{

printf("ERROR, MMAP FAILED!\n");

exit(254);

}

for(count=0; count<1000; count++)

{

if(*(mapped+count)>=97&&*(mapped+count)<=122)

*(mapped+ count)-= 32;

}

msync(mapped, 1000, MS_SYNC);

munmap(mapped,1000);

if(!close(outfile))

{

printf("POSSIBLY SERIOUS ERROR,CLOSE FILE FAILED");

exit(254);

}

return 0;

}

hobby! · 发表于 2004-11-22 12:09:51

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

int main(void)

{

pid_t pid;

if((pid=fork())<0)

{

printf("fork error! \n");

exit(1);

}

else if(pid==0)

{

printf("Child process is printing.\n");

}

else

{

printf("Parent process is printing.\n");

}

exit(0);

}

hobby! · 发表于 2004-11-22 12:16:25

#include <sys/types.h>

#include <stdio.h>

#include <unistd.h>

int main(void)

{

pid_t pid;

if((pid=vfork())<0)

{

printf("fork error! \n");

exit(1);

}

else if(pid==0)

{

printf("Child process is printing.\n");

}

else

{

printf("Parent process is printing.\n");

}

exit(0);

}

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