├── COPYING ├── README.md ├── assets ├── cover.png └── logo.png ├── chapter02 ├── basic-io.c ├── makefile ├── open-file.c ├── read-file.c └── read-stdin.c ├── chapter03 ├── makefile ├── scatter-gather-io.c ├── set-flags.c └── set-lock.c ├── chapter04 ├── makefile └── stat.c ├── chapter05 ├── makefile ├── process_segments.c └── segments_address.c ├── lib ├── common.c ├── common.h ├── common.o ├── libcommon.a └── makefile └── makefile.inc /COPYING: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # LINUX系统编程——煎鱼出品 2 | 3 | **努力更新中。。。** 4 | **努力更新中。。。** 5 | **努力更新中。。。** 6 | 7 | 这是煎鱼大魔王出品《LINUX系统编程》中的源代码 8 | 9 | 所有代码由vim编写，在Archlinux下使用GCC编译调试 10 | 11 | 本教程的文字版请看这：[LINUX系统教程文字版](https://wyattjee.gitbooks.io/linux-os-programming/content/) 12 | 13 | 本教程的视频版请看这：[LINUX系统编程视频版——现在为空链]() 14 | 15 | ![封面](https://github.com/wyattjee/linux-os-programming/blob/master/assets/cover.png) 16 | 17 | ## 关于本书 18 | 19 | Linux是一个很伟大的系统，除了桌面系统占有率不高以外，Linux在各个平台发挥着巨大的作用。了解Linux对工作学习生产都有很大帮助。现在我大中国的Linux爱好者也越来越多，大家也了解了很多Linux系统管理员\(Linux 20 | Sys 21 | Admin\)的相关知识，所以本书从Linux的系统编程为切入点了解Linux，编写Linux下的程序。注意的是本书不是讲解Linux内核的编程，而是Linux提供的系统接口的编程。 22 | 23 | 此外本内容也是为《LINUX系统编程》视频的教程文字版，旨在补充视频教程。本书的全部内容都在Linux环境下完成，logo、书、视频等也是使用Linux下的原生软件创作。 24 | 25 | ## 本书对象 26 | 本书面向的对象不限，但前提是有一定的Linux系统的使用经历，并且有一定的C语言基础。你可以使用自己喜欢的Linux发行版，我主要推荐使用Fedora、Ubuntu或Archlinux作为学习开发的环境。 27 | 28 | * Fedora 29 | > 虽然Fedora上是Redhat试用新技术的地方，但还是十分稳定的，安装方便，Linux之父Linus也是使用Fedora的。 30 | 31 | * Ubuntu 32 | 33 | > 在Linux用户占有一定数量，相关学习资源多，而且是大多开发商开发的平台，当然Google的Goobuntu也是它的衍生版。 34 | 35 | * Archlinux 36 | 37 | > 在众多发行版中不得不说Archlinux是wiki最丰富的，也有很好的包管理软件和aur的补充，及时的软件更新，用来学习开发十分不错。 38 | 39 | ## 关于作者 40 | 41 | 作者为Wyatt Jee，昵称为煎鱼大魔王 42 | 43 | Linux历程：由于破解wifi的原因开始第一次接触了Linux，接触的发行版为cdlinux和backtrack\(现在改名为kali 44 | linux\)，后来因为compiz的炫酷特性开始接触了Ubuntu发行版，也真正开始去了解Linux的相关知识，实在难以想象当初的我一个系统可以折腾一天。和老一辈Linux爱好者不同，他们都是从centos开始的，我想是当时运维大环境下的关系吧。也正是我从Debain系的Ubuntu开始，所以所以习惯了Debain系以及GNOME体验。后来由于Ubuntu的一些问题以及想要对redhat系尝试，开始使用Fedora，体验也还不错，rpm和dnf也很好用。由于系统版本更新的方式使我开始走向滚动更新系，也开始使用了archlinux发行版，也是现在正在使用的主发行版，体验了各大DE\(桌面环境\)和WM\(窗口管理器\)，都很不错。现在的我开始制作Linux相关的学习资料，旨在为Linux和开源界带来新的活力，让更多的人了解学习Linux。 45 | 46 | ## 关于版权 47 | 48 | 本书的封面设计及其logo均由Wyatt 49 | Jee持有不得随意盗用。本书内容供大家个人免费使用，不得转载，如若用于商业用途，请联系作者本人。 50 | 51 | Wyatt Jee (煎鱼大魔王) 52 | 53 | 2016年8月11日，中国浙江 54 | -------------------------------------------------------------------------------- /assets/cover.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/wyattjee/linux-os-programming/1de0a3189c4befee982eb562a4f569581b5d81f1/assets/cover.png -------------------------------------------------------------------------------- /assets/logo.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/wyattjee/linux-os-programming/1de0a3189c4befee982eb562a4f569581b5d81f1/assets/logo.png -------------------------------------------------------------------------------- /chapter02/basic-io.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: basic-io.c 5 | * 6 | * Description: basic io using open() close() write() read() lseek() 7 | * 8 | * Usage: ./basic-io [optrion] file 9 | * -h, --help display this help and exit 10 | * -o, --offset set offset 11 | * -r, --read read part of file 12 | * -w, --write write data to file 13 | * 14 | * Version: 1.0 15 | * Created: 08/13/2016 01:10:38 PM 16 | * Revision: none 17 | * Compiler: gcc 18 | * 19 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 20 | * Organization: JianYuChuPing 21 | * 22 | * ============================================================================= 23 | */ 24 | 25 | #include 26 | #include 27 | #include 28 | #include 29 | #include 30 | #include 31 | #include 32 | #include 33 | #include 34 | 35 | static void usage_error(char *progname); 36 | 37 | int main(int argc, char *argv[]) 38 | { 39 | int fd, opt, j; 40 | off_t offset = 0; 41 | char *buf; 42 | ssize_t num_read, num_write; 43 | size_t opt_read; 44 | int flag_lseek = 0; 45 | int flag_read = 0; 46 | int flag_write = 0; 47 | const char shortopts[] = "ho:r:w:"; 48 | const struct option longopts[] = { 49 | {"help", no_argument, 0, 'h'}, 50 | {"offset", required_argument, 0, 'o'}, 51 | {"read", required_argument, 0, 'r'}, 52 | {"write", required_argument, 0, 'w'}, 53 | {0, 0, 0, 0}, 54 | }; 55 | 56 | 57 | if (argc < 2) { 58 | usage_error(argv[0]); 59 | } 60 | 61 | while ((opt = getopt_long(argc, argv, shortopts, longopts, NULL)) != -1) { 62 | switch (opt) { 63 | case 'h': 64 | usage_error(argv[0]); 65 | case 'o': 66 | flag_lseek = 1; 67 | offset = (off_t) strtol(optarg, NULL, 10); 68 | break; 69 | case 'r': 70 | flag_read = 1; 71 | opt_read = (ssize_t) strtol(optarg, NULL, 10); 72 | break; 73 | case 'w': 74 | flag_write = 1; 75 | buf = optarg; 76 | break; 77 | 78 | case '?': 79 | break; 80 | 81 | default: 82 | fprintf(stderr, "Unexpected error\n"); 83 | exit(EXIT_FAILURE); 84 | } 85 | } 86 | 87 | if ( flag_write && flag_read) { 88 | fprintf(stderr, "don't using read and write at same time\n"); 89 | usage_error(argv[0]); 90 | } 91 | 92 | if (argv[optind] == NULL) { 93 | printf("Choose a file to open\n\n"); 94 | usage_error(argv[0]); 95 | } 96 | 97 | fd = open(argv[optind], O_RDWR | O_CREAT, 98 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); 99 | /* rw-rw-rw- */ 100 | 101 | if (flag_lseek && lseek(fd, offset, SEEK_SET) == -1) { 102 | perror("lseek"); 103 | exit(EXIT_FAILURE); 104 | } 105 | 106 | if (flag_write == 1) { 107 | if ((num_write = write(fd, buf, strlen(buf))) == -1) { 108 | perror("write"); 109 | exit(EXIT_FAILURE); 110 | } 111 | 112 | printf("write succeeded\n"); 113 | 114 | } 115 | 116 | if (flag_read == 1) { 117 | if ((buf = malloc(opt_read)) == NULL) { 118 | perror("malloc"); 119 | exit(EXIT_FAILURE); 120 | } 121 | 122 | if ((num_read = read(fd, buf, opt_read)) == -1) { 123 | perror("read"); 124 | exit(EXIT_FAILURE); 125 | } 126 | 127 | printf("[file]: %s [start position]: %ld\n", argv[optind], offset); 128 | for (j = 0; j < num_read; j++) { 129 | printf("%c", isprint(buf[j]) ? buf[j] : '~'); 130 | } 131 | printf("\n"); 132 | 133 | free(buf); 134 | } 135 | 136 | close(fd); 137 | exit(EXIT_SUCCESS); 138 | } 139 | 140 | 141 | /* 142 | * === FUNCTION ============================================================== 143 | * Name: usage_error 144 | * Description: print usage and exit 145 | * ============================================================================= 146 | */ 147 | 148 | static void usage_error(char *progname) 149 | { 150 | fprintf(stderr, "Usage: %s [optrion] file\n", progname); 151 | fprintf(stderr, " -h, --help display this help and exit\n"); 152 | fprintf(stderr, " -o, --offset set offset\n"); 153 | fprintf(stderr, " -r, --read read part of file\n"); 154 | fprintf(stderr, " -w, --write write data to file\n"); 155 | 156 | exit(EXIT_FAILURE); 157 | } 158 | -------------------------------------------------------------------------------- /chapter02/makefile: -------------------------------------------------------------------------------- 1 | include ../makefile.inc 2 | 3 | EXE = basic-io \ 4 | open-file \ 5 | read-file \ 6 | read-stdin 7 | 8 | all : ${EXE} 9 | 10 | clean : 11 | ${RM} ${EXE} 12 | -------------------------------------------------------------------------------- /chapter02/open-file.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: open-file.c 5 | * 6 | * Description: open a file using open() 7 | * 8 | * Version: 1.0 9 | * Created: 08/13/2016 01:13:01 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include 20 | #include 21 | #include 22 | 23 | #include 24 | #include 25 | #include 26 | 27 | int main(int argc, char *argv[]) 28 | { 29 | int fd; 30 | 31 | fd = open("file", O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR); 32 | if (fd == -1) { 33 | perror("open"); 34 | exit(EXIT_FAILURE); 35 | } 36 | 37 | exit(EXIT_SUCCESS); 38 | } 39 | -------------------------------------------------------------------------------- /chapter02/read-file.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: read-file.c 5 | * 6 | * Description: read from a file using read() 7 | * 8 | * Version: 1.0 9 | * Created: 08/13/2016 01:14:50 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include 20 | #include 21 | #include 22 | #include 23 | 24 | #include 25 | #include 26 | 27 | #define MAX_READ 4096 28 | 29 | int main(int argc, char *argv[]) 30 | { 31 | // variable for read() 32 | char buffer[MAX_READ+1]; 33 | ssize_t num_read; 34 | 35 | // variable for open() 36 | int fd; 37 | 38 | fd = open("open-file.c", O_RDONLY); 39 | if (fd == -1) { 40 | perror("open"); 41 | exit(EXIT_FAILURE); 42 | } 43 | 44 | num_read = read(fd, buffer, MAX_READ); 45 | if (num_read == -1) { 46 | perror("read"); 47 | exit(EXIT_FAILURE); 48 | } 49 | 50 | buffer[num_read] = '\0'; 51 | printf("\n%s\n", buffer); 52 | 53 | exit(EXIT_SUCCESS); 54 | } 55 | -------------------------------------------------------------------------------- /chapter02/read-stdin.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: read-stdin.c 5 | * 6 | * Description: read from standard input using read() 7 | * 8 | * Version: 1.0 9 | * Created: 08/13/2016 01:13:39 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include 20 | 21 | #include 22 | #include 23 | 24 | #define MAX_READ 4096 25 | 26 | int main(int argc, char *argv[]) 27 | { 28 | char buffer[MAX_READ+1]; 29 | ssize_t num_read; 30 | 31 | num_read = read(STDIN_FILENO, buffer, MAX_READ); 32 | if (num_read == -1) { 33 | perror("read"); 34 | exit(EXIT_FAILURE); 35 | } 36 | 37 | buffer[num_read] = '\0'; 38 | 39 | printf("The data you input: %s\n", buffer); 40 | 41 | exit(EXIT_SUCCESS); 42 | } 43 | -------------------------------------------------------------------------------- /chapter03/makefile: -------------------------------------------------------------------------------- 1 | include ../makefile.inc 2 | 3 | EXE = set-flags \ 4 | set-lock \ 5 | scatter-gather-io 6 | 7 | all : ${EXE} 8 | 9 | ${EXE} : ${LIB} 10 | 11 | clean : 12 | ${RM} ${EXE} 13 | -------------------------------------------------------------------------------- /chapter03/scatter-gather-io.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: scatter-gather-io.c 5 | * 6 | * Description: a demonstrate of scatter-gathert I/O 7 | * 8 | * Version: 1.0 9 | * Created: 08/18/2016 03:55:28 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include "common.h" 20 | 21 | #include 22 | #include 23 | #include 24 | 25 | int main(int argc, char *argv[]) 26 | { 27 | int opt; 28 | int fd_read; 29 | int fd_write = STDOUT_FILENO; 30 | ssize_t num_read; 31 | static char buf0[10]; 32 | static char buf1[20]; 33 | static char buf2[30]; 34 | 35 | int iovcnt; 36 | struct iovec iov[3]; 37 | 38 | static struct option long_option[] = { 39 | {"help", no_argument, 0, 'h'}, 40 | {"read", required_argument, 0, 'r'}, 41 | {"write", required_argument, 0, 'w'}, 42 | {0, 0, 0, 0} 43 | }; 44 | 45 | const struct help help[] = { 46 | {'h', "help", "show the usage and exit"}, 47 | {'r', "readv", "readv file"}, 48 | {'w', "writev", "writev file"}, 49 | {0, 0, 0}, 50 | }; 51 | 52 | while ((opt = getopt_long(argc, argv, "hr:w:", long_option, NULL)) != -1) { 53 | switch (opt) { 54 | case 'r': 55 | if ((fd_read = open(optarg, O_RDONLY)) == -1) 56 | err_exit("open file for reading"); 57 | break; 58 | case 'w': 59 | if ((fd_write = open(optarg, O_RDWR)) == -1) 60 | err_exit("open file for writing"); 61 | break; 62 | case 'h': 63 | /* break through */ 64 | default: 65 | usage(help, "Usage: %s -r[file] -w[file]\n", argv[0]); 66 | } 67 | } 68 | 69 | iov[0].iov_base = buf0; 70 | iov[0].iov_len = sizeof(buf0); 71 | iov[1].iov_base = buf1; 72 | iov[1].iov_len = sizeof(buf1); 73 | iov[2].iov_base = buf2; 74 | iov[2].iov_len = sizeof(buf2); 75 | 76 | iovcnt = sizeof(iov) / sizeof(struct iovec); 77 | 78 | if ((num_read = readv(fd_read, iov, iovcnt)) == -1) 79 | err_exit("readv"); 80 | 81 | if ((num_read = writev(fd_write, iov, iovcnt)) == -1) 82 | err_exit("writev"); 83 | 84 | exit(EXIT_SUCCESS); 85 | } 86 | 87 | -------------------------------------------------------------------------------- /chapter03/set-flags.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: set-flags.c 5 | * 6 | * Description: setting the close-on-exec flag 7 | * 8 | * Version: 1.0 9 | * Created: 08/15/2016 03:01:26 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include 20 | #include 21 | #include 22 | #include 23 | 24 | int main(int argc, char *argv[]) 25 | { 26 | int fd; 27 | int flags; 28 | 29 | if ((fd = open("testfile", O_RDWR)) == -1) { 30 | perror("open"); 31 | exit(EXIT_FAILURE); 32 | } 33 | 34 | if ((flags = fcntl(fd, F_GETFL)) == -1) { 35 | perror("fcntl get flags"); 36 | exit(EXIT_FAILURE); 37 | } 38 | 39 | flags |= FD_CLOEXEC; 40 | if (fcntl(fd, F_SETFL, flags) == -1) { 41 | perror("fcntl set flags"); 42 | exit(EXIT_FAILURE); 43 | } 44 | 45 | exit(EXIT_SUCCESS); 46 | } 47 | -------------------------------------------------------------------------------- /chapter03/set-lock.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: set-lock.c 5 | * 6 | * Description: set write lock 7 | * 8 | * Version: 1.0 9 | * Created: 08/15/2016 03:39:46 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include 20 | #include 21 | #include 22 | #include 23 | #include 24 | #include 25 | #include 26 | 27 | int main(int argc, char *argv[]) 28 | { 29 | int fd; 30 | struct flock fl; 31 | 32 | if (argc < 3 || strcmp(argv[1], "--help") == 0) { 33 | fprintf(stderr, "Usage: %s file [option]\n", argv[0]); 34 | fprintf(stderr, " -w lock write\n"); 35 | fprintf(stderr, " -r lock read\n"); 36 | fprintf(stderr, " -u unlock\n"); 37 | exit(EXIT_FAILURE); 38 | } 39 | 40 | if ((fd = open(argv[1], O_RDWR)) == -1) { 41 | perror("open"); 42 | exit(EXIT_FAILURE); 43 | } 44 | 45 | switch (argv[2][1]) { 46 | case 'w': 47 | fl.l_type = F_WRLCK; 48 | fl.l_whence = SEEK_SET; 49 | fl.l_start = 0; 50 | fl.l_len = 0; 51 | break; 52 | case 'r': 53 | fl.l_type = F_RDLCK; 54 | fl.l_whence = SEEK_SET; 55 | fl.l_start = 0; 56 | fl.l_len = 0; 57 | break; 58 | case 'u': 59 | fl.l_type = F_RDLCK; 60 | fl.l_whence = SEEK_SET; 61 | fl.l_start = 0; 62 | fl.l_len = 0; 63 | break; 64 | } 65 | 66 | if (fcntl(fd, F_SETLK, &fl) == -1) { 67 | perror("fcntl set lock"); 68 | exit(EXIT_FAILURE); 69 | } 70 | 71 | exit(EXIT_SUCCESS); 72 | } 73 | -------------------------------------------------------------------------------- /chapter04/makefile: -------------------------------------------------------------------------------- 1 | include ../makefile.inc 2 | 3 | EXE = stat 4 | 5 | all : ${EXE} 6 | 7 | ${EXE} : ${LIB} 8 | 9 | clean : 10 | ${RM} ${EXE} 11 | -------------------------------------------------------------------------------- /chapter04/stat.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: stat.c 5 | * 6 | * Description: a demostration of stat() 7 | * 8 | * Version: 1.0 9 | * Created: 08/24/2016 01:41:34 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | #define _DEFAULT_SOURCE 19 | 20 | #include "common.h" 21 | #include 22 | 23 | static void show_stat( const struct stat *sp ); 24 | 25 | int main(int argc, char *argv[]) 26 | { 27 | struct stat status; 28 | 29 | if (argc != 2 || strcmp(argv[1], "--help") == 0) { 30 | fprintf(stderr, "Usage: %s file\n", argv[0]); 31 | exit(EXIT_FAILURE); 32 | } 33 | 34 | if (stat(argv[1], &status) == -1) { 35 | err_exit("stat\n"); 36 | } 37 | 38 | show_stat(&status); 39 | 40 | exit(EXIT_SUCCESS); 41 | } 42 | 43 | static void show_stat( const struct stat *sp ) 44 | { 45 | fprintf(stdout, "File Type:\t\t"); 46 | 47 | switch (sp->st_mode & S_IFMT) { 48 | case S_IFREG: 49 | fprintf(stdout, "regular file\n"); 50 | break; 51 | case S_IFDIR: 52 | fprintf(stdout, "directory\n"); 53 | break; 54 | case S_IFCHR: 55 | fprintf(stdout, "character device\n"); 56 | break; 57 | case S_IFBLK: 58 | fprintf(stdout, "block device\n"); 59 | break; 60 | case S_IFLNK: 61 | fprintf(stdout, "symbolic link\n"); 62 | break; 63 | case S_IFIFO: 64 | fprintf(stdout, "FIFO or pipe\n"); 65 | break; 66 | case S_IFSOCK: 67 | fprintf(stdout, "socket\n"); 68 | break; 69 | default: 70 | fprintf(stdout, "unknown file type\n"); 71 | break; 72 | } 73 | 74 | fprintf(stdout, "I-node Number:\t\t%ld\n", (long) sp->st_ino); 75 | fprintf(stdout, "Mode:\t\t\t%lo\n", (unsigned long)sp->st_mode); 76 | fprintf(stdout, "Number of link:\t\t%ld\n", (long) sp->st_nlink); 77 | fprintf(stdout, "Oweership:\t\tUID=%ld GID=%ld\n", 78 | (long) sp->st_uid, (long) sp->st_gid); 79 | fprintf(stdout, "File size:\t\t%lld Byte\n", (long long)sp->st_size); 80 | fprintf(stdout, "Optimal IO block size:\t%ld Byte\n", 81 | (long)sp->st_blksize); 82 | fprintf(stdout, "number of block:\t%ld\n", (long) sp->st_blocks); 83 | fprintf(stdout, "Last time access:\t%s", ctime(&sp->st_atime)); 84 | fprintf(stdout, "Last time modify:\t%s", ctime(&sp->st_mtime)); 85 | fprintf(stdout, "Last time chage:\t%s", ctime(&sp->st_ctime)); 86 | } 87 | -------------------------------------------------------------------------------- /chapter05/makefile: -------------------------------------------------------------------------------- 1 | include ../makefile.inc 2 | 3 | EXE = process_segments \ 4 | segments_address 5 | 6 | all : ${EXE} 7 | 8 | ${EXE} : ${LIB} 9 | 10 | clean : 11 | ${RM} ${EXE} 12 | -------------------------------------------------------------------------------- /chapter05/process_segments.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ===================================================================================== 3 | * 4 | * Filename: process_segments.c 5 | * 6 | * Description: demonstrate the mapping between C variable 7 | * and the segment of process. 8 | * 9 | * Version: 1.0 10 | * Created: 07/29/2017 08:28:43 PM 11 | * Revision: none 12 | * Compiler: gcc 13 | * 14 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 15 | * Organization: JianYuChuPing 16 | * 17 | * ===================================================================================== 18 | */ 19 | 20 | #include 21 | #include 22 | 23 | char buffer[2048]; /* Uninitialized data segment */ 24 | int position[] = { 3, 4, 5 }; /* Initialized data segment */ 25 | 26 | static int cube(int num) /* Allocated in frame for cube() */ 27 | { 28 | int result; /* Allocated in frame for cube() */ 29 | 30 | result = num * num * num; 31 | return result; /* return value passed via register */ 32 | } 33 | 34 | static void do_cube(int num) /* Allocated in frame for do_cube() */ 35 | { 36 | if (num > 10 || num < 1) { 37 | fprintf(stderr, "ERROR: Out of Range\n"); 38 | } 39 | else { 40 | for(; num > 0; num--) { 41 | fprintf(stdout, "The cube of %2d is %4d\n", num, cube(num)); 42 | } 43 | } 44 | } 45 | 46 | int main(int argc, char *argv[]) /* Allocated in frame for main() */ 47 | { 48 | static int num = 6; /* Initialized data segment */ 49 | char *ptr; /* Allocated in frame for main() */ 50 | 51 | ptr = malloc(1024); /* Points to memory in heap segment */ 52 | 53 | do_cube(num); 54 | 55 | free(ptr); /* Always remember to free */ 56 | 57 | exit(EXIT_SUCCESS); 58 | } 59 | -------------------------------------------------------------------------------- /chapter05/segments_address.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ===================================================================================== 3 | * 4 | * Filename: segments_address.c 5 | * 6 | * Description: demonstrate the symbol: etext, edata, end 7 | * 8 | * Version: 1.0 9 | * Created: 07/29/2017 09:46:55 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ===================================================================================== 17 | */ 18 | 19 | #include 20 | #include 21 | 22 | extern char etext, edata, end; 23 | 24 | int main(int argc, char *argv[]) 25 | { 26 | fprintf(stdout, "First address past:\n"); 27 | fprintf(stdout, " program text (stdout, etext) %10p\n", &etext); 28 | fprintf(stdout, " initialized data (edata) %10p\n", &edata); 29 | fprintf(stdout, " uninitialized data (end) %10p\n", &end); 30 | 31 | exit(EXIT_SUCCESS); 32 | } 33 | -------------------------------------------------------------------------------- /lib/common.c: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: common.c 5 | * 6 | * Description: some common function 7 | * 8 | * Version: 1.0 9 | * Created: 08/17/2016 07:13:24 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #include "common.h" 20 | 21 | void err_exit(char *s) 22 | { 23 | perror(s); 24 | exit(EXIT_FAILURE); 25 | } 26 | 27 | void usage(const struct help *help, const char *format, ...) 28 | { 29 | int j; 30 | va_list ap; 31 | 32 | fflush(stdout); 33 | va_start(ap, format); 34 | vfprintf(stderr, format, ap); 35 | va_end(ap); 36 | 37 | if (help[0].long_opt == NULL) { 38 | for (j = 0; help[j].short_opt != 0; j++) { 39 | fprintf(stderr, " -%c\t%s\n", help[j].short_opt, 40 | help[j].description); 41 | } 42 | } 43 | else { 44 | for (j = 0; help[j].short_opt != 0; j++) { 45 | fprintf(stderr, " -%c, --%s\t%s\n", help[j].short_opt, 46 | help[j].long_opt, help[j].description); 47 | } 48 | } 49 | 50 | fflush(stderr); 51 | 52 | exit(EXIT_FAILURE); 53 | } 54 | -------------------------------------------------------------------------------- /lib/common.h: -------------------------------------------------------------------------------- 1 | /* 2 | * ============================================================================= 3 | * 4 | * Filename: common.h 5 | * 6 | * Description: common include file 7 | * 8 | * Version: 1.0 9 | * Created: 08/17/2016 05:14:45 PM 10 | * Revision: none 11 | * Compiler: gcc 12 | * 13 | * Author: Wyatt Jee (WJ), bluesorrow221@gmail.com 14 | * Organization: JianYuChuPing 15 | * 16 | * ============================================================================= 17 | */ 18 | 19 | #ifndef COMMON_H 20 | #define COMMON_H 21 | 22 | #include 23 | #include 24 | #include 25 | #include 26 | #include 27 | #include 28 | #include 29 | 30 | typedef enum { FALSE, TRUE } boolen; 31 | 32 | struct help { 33 | char short_opt; 34 | const char *long_opt; 35 | const char *description; 36 | }; 37 | 38 | void err_exit(char *s); 39 | void usage(const struct help *help, const char *format, ...); 40 | 41 | #endif 42 | -------------------------------------------------------------------------------- /lib/common.o: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/wyattjee/linux-os-programming/1de0a3189c4befee982eb562a4f569581b5d81f1/lib/common.o -------------------------------------------------------------------------------- /lib/libcommon.a: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/wyattjee/linux-os-programming/1de0a3189c4befee982eb562a4f569581b5d81f1/lib/libcommon.a -------------------------------------------------------------------------------- /lib/makefile: -------------------------------------------------------------------------------- 1 | include ../makefile.inc 2 | 3 | all : ${LIB} 4 | 5 | ${LIB} : *.c 6 | ${CC} -c -g ${CFLAGS} *.c 7 | ${AR} rs ${LIB} *.o 8 | 9 | clean : 10 | ${RM} *.o ${LIB} 11 | -------------------------------------------------------------------------------- /makefile.inc: -------------------------------------------------------------------------------- 1 | # This is the common definitions using by subdir makefiles 2 | 3 | ROOT = .. 4 | LIB_DIR = ${ROOT}/lib 5 | LIB = ${LIB_DIR}/libcommon.a 6 | 7 | CFLAGS = -std=c99 \ 8 | -g -I${LIB_DIR} \ 9 | -Wall \ 10 | 11 | RM = rm -f 12 | --------------------------------------------------------------------------------