unp.h的安装以及第一个程序的运行
unp.h的安装以及第一个程序的运行
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源代码下载以及编译
解压到本地文件夹，如果访问不了GitHub的话就用我搬到gitee的仓库吧
git clone https://gitee.com/Find-ing/unpv13e.git直接这样就不用解压了
这里可以看看README
按照README上的顺序
首先执行
./configure然后
cd lib make cd ../libfree make cd ../libroute make如果出现了错误，就再来一次
cd ../lib make cd ../libfree make cd ../libroute make第二遍做完之后，如果出现了如下错误：
[root@docker libfree]# cd ../libroute [root@docker libroute]# make gcc -I../lib -g -O2 -D_REENTRANT -Wall -c -o get_rtaddrs.o get_rtaddrs.c In file included from get_rtaddrs.c:1: unproute.h:3:10: fatal error: net/if_dl.h: No such file or directory #include <net/if_dl.h> /* sockaddr_sdl{} */ ^~~~~~~~~~~~~ compilation terminated. make: *** [<builtin>: get_rtaddrs.o] Error 1哈哈哈，看了半天教程，改了好久也没搞好，仔细看看README，我真是
好，仔细看看README怎么说的
> cd ../libroute # only if your system supports 4.4BSD style routing sockets
> make # only if your system supports 4.4BSD style routing sockets
<font color='red'>only if your system supports 4.4BSD style routing sockets</font>
okok，下一步
可以看到内容已经被编译到unpv13e/libunp.a里面去了
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拷贝
sudo cp libunp.a /usr/lib sudo cp libunp.a /usr/lib64 # 有的系统可能没有这个文件夹，那就不用拷贝这个了，反正我的有在
.\lib\unp.h中将#include "../config.h"改为#include "config.h"然后
sudo cp config.h /usr/include sudo cp lib/unp.h /usr/include -
现在是第三阶段，因为我们在运行代码时会报一个错
/tmp/ccM5DNZP.o: In function `main': test.c:(.text+0x2c): undefined reference to `err_quit' test.c:(.text+0x58): undefined reference to `err_sys' test.c:(.text+0xd2): undefined reference to `err_quit' test.c:(.text+0xfe): undefined reference to `err_sys' test.c:(.text+0x13a): undefined reference to `err_sys' test.c:(.text+0x171): undefined reference to `err_sys' collect2: error: ld returned 1 exit status原因是err_quit,err_sys等这些函数都是作者自己定义的函数真正的函数在http://www.apuebook.com/code3e.html下载。
把
error.c的文件名改为myerr.c在
apue.h文件最后一行#endif /* _APUE_H */前加入#include "myerr.c"在
unp.h中加入#include "apue.h"将
apue.h和myerr.c文件都拷贝到/usr/include中去上面这些改改找找的操作各位要是想做就可以做一遍，如果是在不想做，就按照下面的操作
打开
/usr/include然后删除
unp.h里面所有内容，然后复制这一段粘进去/* include unph */ /* Our own header. Tabs are set for 4 spaces, not 8 */ #ifndef __unp_h #define __unp_h #include "apue.h" #include "config.h" /* configuration options for current OS */ /* "../config.h" is generated by configure */ #define MAX_LINE 2048 /* If anything changes in the following list of #includes, must change acsite.m4 also, for configure's tests. */ #include <sys/types.h> /* basic system data types */ #include <sys/socket.h> /* basic socket definitions */ #if TIME_WITH_SYS_TIME #include <sys/time.h> /* timeval{} for select() */ #include <time.h> /* timespec{} for pselect() */ #else #if HAVE_SYS_TIME_H #include <sys/time.h> /* includes <time.h> unsafely */ #else #include <time.h> /* old system? */ #endif #endif #include <netinet/in.h> /* sockaddr_in{} and other Internet defns */ #include <arpa/inet.h> /* inet(3) functions */ #include <errno.h> #include <fcntl.h> /* for nonblocking */ #include <netdb.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> /* for S_xxx file mode constants */ #include <sys/uio.h> /* for iovec{} and readv/writev */ #include <unistd.h> #include <sys/wait.h> #include <sys/un.h> /* for Unix domain sockets */ #ifdef HAVE_SYS_SELECT_H # include <sys/select.h> /* for convenience */ #endif #ifdef HAVE_SYS_SYSCTL_H #ifdef HAVE_SYS_PARAM_H # include <sys/param.h> /* OpenBSD prereq for sysctl.h */ #endif # include <sys/sysctl.h> #endif #ifdef HAVE_POLL_H # include <poll.h> /* for convenience */ #endif #ifdef HAVE_SYS_EVENT_H # include <sys/event.h> /* for kqueue */ #endif #ifdef HAVE_STRINGS_H # include <strings.h> /* for convenience */ #endif /* Three headers are normally needed for socket/file ioctl's: * <sys/ioctl.h>, <sys/filio.h>, and <sys/sockio.h>. */ #ifdef HAVE_SYS_IOCTL_H # include <sys/ioctl.h> #endif #ifdef HAVE_SYS_FILIO_H # include <sys/filio.h> #endif #ifdef HAVE_SYS_SOCKIO_H # include <sys/sockio.h> #endif #ifdef HAVE_PTHREAD_H # include <pthread.h> #endif #ifdef HAVE_NET_IF_DL_H # include <net/if_dl.h> #endif #ifdef HAVE_NETINET_SCTP_H #include <netinet/sctp.h> #endif /* OSF/1 actually disables recv() and send() in <sys/socket.h> */ #ifdef __osf__ #undef recv #undef send #define recv(a,b,c,d) recvfrom(a,b,c,d,0,0) #define send(a,b,c,d) sendto(a,b,c,d,0,0) #endif #ifndef INADDR_NONE /* $$.Ic INADDR_NONE$$ */ #define INADDR_NONE 0xffffffff /* should have been in <netinet/in.h> */ #endif #ifndef SHUT_RD /* these three POSIX names are new */ #define SHUT_RD 0 /* shutdown for reading */ #define SHUT_WR 1 /* shutdown for writing */ #define SHUT_RDWR 2 /* shutdown for reading and writing */ /* $$.Ic SHUT_RD$$ */ /* $$.Ic SHUT_WR$$ */ /* $$.Ic SHUT_RDWR$$ */ #endif /* *INDENT-OFF* */ #ifndef INET_ADDRSTRLEN /* $$.Ic INET_ADDRSTRLEN$$ */ #define INET_ADDRSTRLEN 16 /* "ddd.ddd.ddd.ddd\0" 1234567890123456 */ #endif /* Define following even if IPv6 not supported, so we can always allocate an adequately sized buffer without #ifdefs in the code. */ #ifndef INET6_ADDRSTRLEN /* $$.Ic INET6_ADDRSTRLEN$$ */ #define INET6_ADDRSTRLEN 46 /* max size of IPv6 address string: "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx" or "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:ddd.ddd.ddd.ddd\0" 1234567890123456789012345678901234567890123456 */ #endif /* *INDENT-ON* */ /* Define bzero() as a macro if it's not in standard C library. */ #ifndef HAVE_BZERO #define bzero(ptr,n) memset(ptr, 0, n) /* $$.If bzero$$ */ /* $$.If memset$$ */ #endif /* Older resolvers do not have gethostbyname2() */ #ifndef HAVE_GETHOSTBYNAME2 #define gethostbyname2(host,family) gethostbyname((host)) #endif /* The structure returned by recvfrom_flags() */ struct unp_in_pktinfo { struct in_addr ipi_addr; /* dst IPv4 address */ int ipi_ifindex;/* received interface index */ }; /* $$.It unp_in_pktinfo$$ */ /* $$.Ib ipi_addr$$ */ /* $$.Ib ipi_ifindex$$ */ /* We need the newer CMSG_LEN() and CMSG_SPACE() macros, but few implementations support them today. These two macros really need an ALIGN() macro, but each implementation does this differently. */ #ifndef CMSG_LEN /* $$.Im CMSG_LEN$$ */ #define CMSG_LEN(size) (sizeof(struct cmsghdr) + (size)) #endif #ifndef CMSG_SPACE /* $$.Im CMSG_SPACE$$ */ #define CMSG_SPACE(size) (sizeof(struct cmsghdr) + (size)) #endif /* POSIX requires the SUN_LEN() macro, but not all implementations DefinE it (yet). Note that this 4.4BSD macro works regardless whether there is a length field or not. */ #ifndef SUN_LEN /* $$.Im SUN_LEN$$ */ # define SUN_LEN(su) \ (sizeof(*(su)) - sizeof((su)->sun_path) + strlen((su)->sun_path)) #endif /* POSIX renames "Unix domain" as "local IPC." Not all systems DefinE AF_LOCAL and PF_LOCAL (yet). */ #ifndef AF_LOCAL #define AF_LOCAL AF_UNIX #endif #ifndef PF_LOCAL #define PF_LOCAL PF_UNIX #endif /* POSIX requires that an #include of <poll.h> DefinE INFTIM, but many systems still DefinE it in <sys/stropts.h>. We don't want to include all the STREAMS stuff if it's not needed, so we just DefinE INFTIM here. This is the standard value, but there's no guarantee it is -1. */ #ifndef INFTIM #define INFTIM (-1) /* infinite poll timeout */ /* $$.Ic INFTIM$$ */ #ifdef HAVE_POLL_H #define INFTIM_UNPH /* tell unpxti.h we defined it */ #endif #endif /* Following could be derived from SOMAXCONN in <sys/socket.h>, but many kernels still #define it as 5, while actually supporting many more */ #define LISTENQ 1024 /* 2nd argument to listen() */ /* Miscellaneous constants */ #define MAXLINE 4096 /* max text line length */ #define BUFFSIZE 8192 /* buffer size for reads and writes */ /* Define some port number that can be used for our examples */ #define SERV_PORT 9877 /* TCP and UDP */ #define SERV_PORT_STR "9877" /* TCP and UDP */ #define UNIXSTR_PATH "/tmp/unix.str" /* Unix domain stream */ #define UNIXDG_PATH "/tmp/unix.dg" /* Unix domain datagram */ /* $$.ix [LISTENQ]~constant,~definition~of$$ */ /* $$.ix [MAXLINE]~constant,~definition~of$$ */ /* $$.ix [BUFFSIZE]~constant,~definition~of$$ */ /* $$.ix [SERV_PORT]~constant,~definition~of$$ */ /* $$.ix [UNIXSTR_PATH]~constant,~definition~of$$ */ /* $$.ix [UNIXDG_PATH]~constant,~definition~of$$ */ /* Following shortens all the typecasts of pointer arguments: */ #define SA struct sockaddr #ifndef HAVE_STRUCT_SOCKADDR_STORAGE /* * RFC 3493: protocol-independent placeholder for socket addresses */ #define __SS_MAXSIZE 128 #define __SS_ALIGNSIZE (sizeof(int64_t)) #ifdef HAVE_SOCKADDR_SA_LEN #define __SS_PAD1SIZE (__SS_ALIGNSIZE - sizeof(u_char) - sizeof(sa_family_t)) #else #define __SS_PAD1SIZE (__SS_ALIGNSIZE - sizeof(sa_family_t)) #endif #define __SS_PAD2SIZE (__SS_MAXSIZE - 2*__SS_ALIGNSIZE) struct sockaddr_storage { #ifdef HAVE_SOCKADDR_SA_LEN u_char ss_len; #endif sa_family_t ss_family; char __ss_pad1[__SS_PAD1SIZE]; int64_t __ss_align; char __ss_pad2[__SS_PAD2SIZE]; }; #endif #define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) /* default file access permissions for new files */ #define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH) /* default permissions for new directories */ typedef void Sigfunc(int); /* for signal handlers */ #define min(a,b) ((a) < (b) ? (a) : (b)) #define max(a,b) ((a) > (b) ? (a) : (b)) #ifndef HAVE_ADDRINFO_STRUCT # include "../lib/addrinfo.h" #endif #ifndef HAVE_IF_NAMEINDEX_STRUCT struct if_nameindex { unsigned int if_index; /* 1, 2, ... */ char *if_name; /* null-terminated name: "le0", ... */ }; /* $$.It if_nameindex$$ */ /* $$.Ib if_index$$ */ /* $$.Ib if_name$$ */ #endif #ifndef HAVE_TIMESPEC_STRUCT struct timespec { time_t tv_sec; /* seconds */ long tv_nsec; /* and nanoseconds */ }; /* $$.It timespec$$ */ /* $$.Ib tv_sec$$ */ /* $$.Ib tv_nsec$$ */ #endif /* end unph */ /* prototypes for our own library functions */ int connect_nonb(int, const SA *, socklen_t, int); int connect_timeo(int, const SA *, socklen_t, int); int daemon_init(const char *, int); void daemon_inetd(const char *, int); void dg_cli(FILE *, int, const SA *, socklen_t); void dg_echo(int, SA *, socklen_t); int family_to_level(int); char *gf_time(void); void heartbeat_cli(int, int, int); void heartbeat_serv(int, int, int); struct addrinfo *host_serv(const char *, const char *, int, int); int inet_srcrt_add(char *); u_char *inet_srcrt_init(int); void inet_srcrt_print(u_char *, int); void inet6_srcrt_print(void *); char **my_addrs(int *); int readable_timeo(int, int); ssize_t readline(int, void *, size_t); ssize_t readn(int, void *, size_t); ssize_t read_fd(int, void *, size_t, int *); ssize_t recvfrom_flags(int, void *, size_t, int *, SA *, socklen_t *, struct unp_in_pktinfo *); Sigfunc *signal_intr(int, Sigfunc *); int sock_bind_wild(int, int); int sock_cmp_addr(const SA *, const SA *, socklen_t); int sock_cmp_port(const SA *, const SA *, socklen_t); int sock_get_port(const SA *, socklen_t); void sock_set_addr(SA *, socklen_t, const void *); void sock_set_port(SA *, socklen_t, int); void sock_set_wild(SA *, socklen_t); char *sock_ntop(const SA *, socklen_t); char *sock_ntop_host(const SA *, socklen_t); int sockfd_to_family(int); void str_echo(int); void str_cli(FILE *, int); int tcp_connect(const char *, const char *); int tcp_listen(const char *, const char *, socklen_t *); void tv_sub(struct timeval *, struct timeval *); int udp_client(const char *, const char *, SA **, socklen_t *); int udp_connect(const char *, const char *); int udp_server(const char *, const char *, socklen_t *); int writable_timeo(int, int); ssize_t writen(int, const void *, size_t); ssize_t write_fd(int, void *, size_t, int); #ifdef MCAST int mcast_leave(int, const SA *, socklen_t); int mcast_join(int, const SA *, socklen_t, const char *, u_int); int mcast_leave_source_group(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); int mcast_join_source_group(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen, const char *ifname, u_int ifindex); int mcast_block_source(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); int mcast_unblock_source(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); int mcast_get_if(int); int mcast_get_loop(int); int mcast_get_ttl(int); int mcast_set_if(int, const char *, u_int); int mcast_set_loop(int, int); int mcast_set_ttl(int, int); void Mcast_leave(int, const SA *, socklen_t); void Mcast_join(int, const SA *, socklen_t, const char *, u_int); void Mcast_leave_source_group(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); void Mcast_join_source_group(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen, const char *ifname, u_int ifindex); void Mcast_block_source(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); void Mcast_unblock_source(int sockfd, const SA *src, socklen_t srclen, const SA *grp, socklen_t grplen); int Mcast_get_if(int); int Mcast_get_loop(int); int Mcast_get_ttl(int); void Mcast_set_if(int, const char *, u_int); void Mcast_set_loop(int, int); void Mcast_set_ttl(int, int); #endif uint16_t in_cksum(uint16_t *, int); #ifndef HAVE_GETADDRINFO_PROTO int getaddrinfo(const char *, const char *, const struct addrinfo *, struct addrinfo **); void freeaddrinfo(struct addrinfo *); char *gai_strerror(int); #endif #ifndef HAVE_GETNAMEINFO_PROTO int getnameinfo(const SA *, socklen_t, char *, size_t, char *, size_t, int); #endif #ifndef HAVE_GETHOSTNAME_PROTO int gethostname(char *, int); #endif #ifndef HAVE_HSTRERROR_PROTO const char *hstrerror(int); #endif #ifndef HAVE_IF_NAMETOINDEX_PROTO unsigned int if_nametoindex(const char *); char *if_indextoname(unsigned int, char *); void if_freenameindex(struct if_nameindex *); struct if_nameindex *if_nameindex(void); #endif #ifndef HAVE_INET_PTON_PROTO int inet_pton(int, const char *, void *); const char *inet_ntop(int, const void *, char *, size_t); #endif #ifndef HAVE_INET_ATON_PROTO int inet_aton(const char *, struct in_addr *); #endif #ifndef HAVE_PSELECT_PROTO int pselect(int, fd_set *, fd_set *, fd_set *, const struct timespec *, const sigset_t *); #endif #ifndef HAVE_SOCKATMARK_PROTO int sockatmark(int); #endif #ifndef HAVE_SNPRINTF_PROTO int snprintf(char *, size_t, const char *, ...); #endif /* prototypes for our own library wrapper functions */ void Connect_timeo(int, const SA *, socklen_t, int); int Family_to_level(int); struct addrinfo *Host_serv(const char *, const char *, int, int); const char *Inet_ntop(int, const void *, char *, size_t); void Inet_pton(int, const char *, void *); char *If_indextoname(unsigned int, char *); unsigned int If_nametoindex(const char *); struct if_nameindex *If_nameindex(void); char **My_addrs(int *); ssize_t Read_fd(int, void *, size_t, int *); int Readable_timeo(int, int); ssize_t Recvfrom_flags(int, void *, size_t, int *, SA *, socklen_t *, struct unp_in_pktinfo *); Sigfunc *Signal(int, Sigfunc *); Sigfunc *Signal_intr(int, Sigfunc *); int Sock_bind_wild(int, int); char *Sock_ntop(const SA *, socklen_t); char *Sock_ntop_host(const SA *, socklen_t); int Sockfd_to_family(int); int Tcp_connect(const char *, const char *); int Tcp_listen(const char *, const char *, socklen_t *); int Udp_client(const char *, const char *, SA **, socklen_t *); int Udp_connect(const char *, const char *); int Udp_server(const char *, const char *, socklen_t *); ssize_t Write_fd(int, void *, size_t, int); int Writable_timeo(int, int); /* prototypes for our Unix wrapper functions: see {Sec errors} */ void *Calloc(size_t, size_t); void Close(int); void Dup2(int, int); int Fcntl(int, int, int); void Gettimeofday(struct timeval *, void *); int Ioctl(int, int, void *); pid_t Fork(void); void *Malloc(size_t); int Mkstemp(char *); void *Mmap(void *, size_t, int, int, int, off_t); int Open(const char *, int, mode_t); void Pipe(int *fds); ssize_t Read(int, void *, size_t); void Sigaddset(sigset_t *, int); void Sigdelset(sigset_t *, int); void Sigemptyset(sigset_t *); void Sigfillset(sigset_t *); int Sigismember(const sigset_t *, int); void Sigpending(sigset_t *); void Sigprocmask(int, const sigset_t *, sigset_t *); char *Strdup(const char *); long Sysconf(int); void Sysctl(int *, u_int, void *, size_t *, void *, size_t); void Unlink(const char *); pid_t Wait(int *); pid_t Waitpid(pid_t, int *, int); void Write(int, void *, size_t); /* prototypes for our stdio wrapper functions: see {Sec errors} */ void Fclose(FILE *); FILE *Fdopen(int, const char *); char *Fgets(char *, int, FILE *); FILE *Fopen(const char *, const char *); void Fputs(const char *, FILE *); /* prototypes for our socket wrapper functions: see {Sec errors} */ int Accept(int, SA *, socklen_t *); void Bind(int, const SA *, socklen_t); void Connect(int, const SA *, socklen_t); void Getpeername(int, SA *, socklen_t *); void Getsockname(int, SA *, socklen_t *); void Getsockopt(int, int, int, void *, socklen_t *); #ifdef HAVE_INET6_RTH_INIT int Inet6_rth_space(int, int); void *Inet6_rth_init(void *, socklen_t, int, int); void Inet6_rth_add(void *, const struct in6_addr *); void Inet6_rth_reverse(const void *, void *); int Inet6_rth_segments(const void *); struct in6_addr *Inet6_rth_getaddr(const void *, int); #endif #ifdef HAVE_KQUEUE int Kqueue(void); int Kevent(int, const struct kevent *, int, struct kevent *, int, const struct timespec *); #endif void Listen(int, int); #ifdef HAVE_POLL int Poll(struct pollfd *, unsigned long, int); #endif ssize_t Readline(int, void *, size_t); ssize_t Readn(int, void *, size_t); ssize_t Recv(int, void *, size_t, int); ssize_t Recvfrom(int, void *, size_t, int, SA *, socklen_t *); ssize_t Recvmsg(int, struct msghdr *, int); int Select(int, fd_set *, fd_set *, fd_set *, struct timeval *); void Send(int, const void *, size_t, int); void Sendto(int, const void *, size_t, int, const SA *, socklen_t); void Sendmsg(int, const struct msghdr *, int); void Setsockopt(int, int, int, const void *, socklen_t); void Shutdown(int, int); int Sockatmark(int); int Socket(int, int, int); void Socketpair(int, int, int, int *); void Writen(int, void *, size_t); void err_dump(const char *, ...); void err_msg(const char *, ...); void err_quit(const char *, ...); void err_ret(const char *, ...); void err_sys(const char *, ...); #endif /* __unp_h */新建一个
apue.h，把下面这段粘贴进去/* * Our own header, to be included before all standard system headers. */ #ifndef _APUE_H #define _APUE_H #define _POSIX_C_SOURCE 200809L #if defined(SOLARIS) /* Solaris 10 */ #define _XOPEN_SOURCE 600 #else #define _XOPEN_SOURCE 700 #endif #include <sys/types.h> /* some systems still require this */ #include <sys/stat.h> #include <sys/termios.h> /* for winsize */ #if defined(MACOS) || !defined(TIOCGWINSZ) #include <sys/ioctl.h> #endif #include <stdio.h> /* for convenience */ #include <stdlib.h> /* for convenience */ #include <stddef.h> /* for offsetof */ #include <string.h> /* for convenience */ #include <unistd.h> /* for convenience */ #include <signal.h> /* for SIG_ERR */ #define MAXLINE 4096 /* max line length */ /* * Default file access permissions for new files. */ #define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) /* * Default permissions for new directories. */ #define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH) typedef void Sigfunc(int); /* for signal handlers */ #define min(a,b) ((a) < (b) ? (a) : (b)) #define max(a,b) ((a) > (b) ? (a) : (b)) /* * Prototypes for our own functions. */ char *path_alloc(size_t *); /* {Prog pathalloc} */ long open_max(void); /* {Prog openmax} */ int set_cloexec(int); /* {Prog setfd} */ void clr_fl(int, int); void set_fl(int, int); /* {Prog setfl} */ void pr_exit(int); /* {Prog prexit} */ void pr_mask(const char *); /* {Prog prmask} */ Sigfunc *signal_intr(int, Sigfunc *); /* {Prog signal_intr_function} */ void daemonize(const char *); /* {Prog daemoninit} */ void sleep_us(unsigned int); /* {Ex sleepus} */ ssize_t readn(int, void *, size_t); /* {Prog readn_writen} */ ssize_t writen(int, const void *, size_t); /* {Prog readn_writen} */ int fd_pipe(int *); /* {Prog sock_fdpipe} */ int recv_fd(int, ssize_t (*func)(int, const void *, size_t)); /* {Prog recvfd_sockets} */ int send_fd(int, int); /* {Prog sendfd_sockets} */ int send_err(int, int, const char *); /* {Prog senderr} */ int serv_listen(const char *); /* {Prog servlisten_sockets} */ int serv_accept(int, uid_t *); /* {Prog servaccept_sockets} */ int cli_conn(const char *); /* {Prog cliconn_sockets} */ int buf_args(char *, int (*func)(int, char **)); /* {Prog bufargs} */ int tty_cbreak(int); /* {Prog raw} */ int tty_raw(int); /* {Prog raw} */ int tty_reset(int); /* {Prog raw} */ void tty_atexit(void); /* {Prog raw} */ struct termios *tty_termios(void); /* {Prog raw} */ int ptym_open(char *, int); /* {Prog ptyopen} */ int ptys_open(char *); /* {Prog ptyopen} */ #ifdef TIOCGWINSZ pid_t pty_fork(int *, char *, int, const struct termios *, const struct winsize *); /* {Prog ptyfork} */ #endif int lock_reg(int, int, int, off_t, int, off_t); /* {Prog lockreg} */ #define read_lock(fd, offset, whence, len) \ lock_reg((fd), F_SETLK, F_RDLCK, (offset), (whence), (len)) #define readw_lock(fd, offset, whence, len) \ lock_reg((fd), F_SETLKW, F_RDLCK, (offset), (whence), (len)) #define write_lock(fd, offset, whence, len) \ lock_reg((fd), F_SETLK, F_WRLCK, (offset), (whence), (len)) #define writew_lock(fd, offset, whence, len) \ lock_reg((fd), F_SETLKW, F_WRLCK, (offset), (whence), (len)) #define un_lock(fd, offset, whence, len) \ lock_reg((fd), F_SETLK, F_UNLCK, (offset), (whence), (len)) pid_t lock_test(int, int, off_t, int, off_t); /* {Prog locktest} */ #define is_read_lockable(fd, offset, whence, len) \ (lock_test((fd), F_RDLCK, (offset), (whence), (len)) == 0) #define is_write_lockable(fd, offset, whence, len) \ (lock_test((fd), F_WRLCK, (offset), (whence), (len)) == 0) void err_msg(const char *, ...); /* {App misc_source} */ void err_dump(const char *, ...) __attribute__((noreturn)); void err_quit(const char *, ...) __attribute__((noreturn)); void err_cont(int, const char *, ...); void err_exit(int, const char *, ...) __attribute__((noreturn)); void err_ret(const char *, ...); void err_sys(const char *, ...) __attribute__((noreturn)); void log_msg(const char *, ...); /* {App misc_source} */ void log_open(const char *, int, int); void log_quit(const char *, ...) __attribute__((noreturn)); void log_ret(const char *, ...); void log_sys(const char *, ...) __attribute__((noreturn)); void log_exit(int, const char *, ...) __attribute__((noreturn)); void TELL_WAIT(void); /* parent/child from {Sec race_conditions} */ void TELL_PARENT(pid_t); void TELL_CHILD(pid_t); void WAIT_PARENT(void); void WAIT_CHILD(void); #include "myerr.c" #endif /* _APUE_H */再新建一个
myerr.c，把下面内容填充进去#include "apue.h" #include <errno.h> /* for definition of errno */ #include <stdarg.h> /* ISO C variable aruments */ static void err_doit(int, int, const char *, va_list); /* * Nonfatal error related to a system call. * Print a message and return. */ void err_ret(const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(1, errno, fmt, ap); va_end(ap); } /* * Fatal error related to a system call. * Print a message and terminate. */ void err_sys(const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(1, errno, fmt, ap); va_end(ap); exit(1); } /* * Nonfatal error unrelated to a system call. * Error code passed as explict parameter. * Print a message and return. */ void err_cont(int error, const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(1, error, fmt, ap); va_end(ap); } /* * Fatal error unrelated to a system call. * Error code passed as explict parameter. * Print a message and terminate. */ void err_exit(int error, const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(1, error, fmt, ap); va_end(ap); exit(1); } /* * Fatal error related to a system call. * Print a message, dump core, and terminate. */ void err_dump(const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(1, errno, fmt, ap); va_end(ap); abort(); /* dump core and terminate */ exit(1); /* shouldn't get here */ } /* * Nonfatal error unrelated to a system call. * Print a message and return. */ void err_msg(const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(0, 0, fmt, ap); va_end(ap); } /* * Fatal error unrelated to a system call. * Print a message and terminate. */ void err_quit(const char *fmt, ...) { va_list ap; va_start(ap, fmt); err_doit(0, 0, fmt, ap); va_end(ap); exit(1); } /* * Print a message and return to caller. * Caller specifies "errnoflag". */ static void err_doit(int errnoflag, int error, const char *fmt, va_list ap) { char buf[MAXLINE]; vsnprintf(buf, MAXLINE-1, fmt, ap); if (errnoflag) snprintf(buf+strlen(buf), MAXLINE-strlen(buf)-1, ": %s", strerror(error)); strcat(buf, "\n"); fflush(stdout); /* in case stdout and stderr are the same */ fputs(buf, stderr); fflush(NULL); /* flushes all stdio output streams */ }
然后编译就成功了
然后运行就失败了
解决方案：
sudo apt-get install xinetd
# sudo yum install xinetd
vi /etc/xinetd.d/daytime
把disable = yes改成disable = no
service daytime
{
disable = no
type = INTERNA:L
id = daytime-stream
socket_type = stream
protocol = tcp
user = root
wait = no
}
接下来：
sudo service xinetd reload
netstat -a -t | grep daytime # 确认服务正在运行
如果不行，报错了，就看看这篇照着做肯定行https://www.cnblogs.com/yewandemty/p/5396391.html（一般centOS可能会报错，Ubuntu一般不会报错）
照着做完之后代码运行成功：
我运行的代码：
#include "unp.h"
int
main(int argc, char **argv)
{
int sockfd, n;
char recvline[MAXLINE + 1];
struct sockaddr_in servaddr;
if (argc != 2)
err_quit("usage: a.out <IPaddress>");
if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
err_sys("socket error");
bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(13); /* daytime server */
if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0)
err_quit("inet_pton error for %s", argv[1]);
if (connect(sockfd, (SA *) &servaddr, sizeof(servaddr)) < 0)
err_sys("connect error");
while ( (n = read(sockfd, recvline, MAXLINE)) > 0) {
recvline[n] = 0; /* null terminate */
if (fputs(recvline, stdout) == EOF)
err_sys("fputs error");
}
if (n < 0)
err_sys("read error");
exit(0);
}
