UNIX Network Programming (Volume 1) first program compilation process

The UNIX volume I bought last summer has only begun to look very ashamed, and I am ashamed that the first program has been on and off for a few days, so I have to write a program, and I am looking for a job soon, the following describes how to run the first program in this book:

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I use Ubuntu 13.04 as the system.

Thanks to the blog: After the portal, you must record your various problems and solutions. When we are new to a field, I often have a lot of time delay in getting started. I still have a problem after I have prepared everything in a good way.

Kapop @ kapop :~ /CPP $ g ++. CPP-o a-lunp/tmp/cczlhmnw. o: In the 'main' function:. CPP :(. text + 0x30): For 'err _ quit (char const *,...) 'undefined reference. CPP :(. text + 0x67): For 'err _ sys (char const *,...) 'undefined reference. CPP :(. text + 0xd9): For 'err _ quit (char const *,...) 'undefined reference. CPP :(. text + 0x108): For 'err _ sys (char const *,...) 'undefined reference. CPP :(. text + 0x142): For 'err _ sys (char const *,...) 'undefined reference. CPP :(. text + 0x181): For 'err _ sys (char const *,...) 'undefined reference collect2: Error: LD returns 1 Kapo P @ kapop :~ /CPP $ g ++ A. cpp unp. C-o a-lunpkapop @ kapop :~ /CPP $./A 127.0.0.103 Aug 2013 15:53:32 CST

The content of the UNP. c file is as follows:

#include<errno.h>/* for definition of errno */#include<stdarg.h>/* ANSI C header file *///#include"ourhdr.h"#include    "unp.h"static voiderr_doit(int, const char *, va_list);char*pname = NULL;/* caller can set this from argv[0] *//* Nonfatal error related to a system call. * Print a message and return. */void/* $f err_ret $ */err_ret(const char *fmt, ...){va_listap;va_start(ap, fmt);err_doit(1, fmt, ap);va_end(ap);return;}/* Fatal error related to a system call. * Print a message and terminate. */void/* $f err_sys $ */err_sys(const char *fmt, ...){va_listap;va_start(ap, fmt);err_doit(1, fmt, ap);va_end(ap);exit(1);}/* Fatal error related to a system call. * Print a message, dump core, and terminate. */void/* $f err_dump $ */err_dump(const char *fmt, ...){va_listap;va_start(ap, fmt);err_doit(1, 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/* $f err_msg $ */err_msg(const char *fmt, ...){va_listap;va_start(ap, fmt);err_doit(0, fmt, ap);va_end(ap);return;}/* Fatal error unrelated to a system call. * Print a message and terminate. */void/* $f err_quit $ */err_quit(const char *fmt, ...){va_listap;va_start(ap, fmt);err_doit(0, fmt, ap);va_end(ap);exit(1);}/* Print a message and return to caller. * Caller specifies "errnoflag". */static voiderr_doit(int errnoflag, const char *fmt, va_list ap){interrno_save;charbuf[MAXLINE];errno_save = errno;/* value caller might want printed */vsprintf(buf, fmt, ap);if (errnoflag)sprintf(buf+strlen(buf), ": %s", strerror(errno_save));strcat(buf, "\n");fflush(stdout);/* in case stdout and stderr are the same */fputs(buf, stderr);fflush(stderr);/* SunOS 4.1.* doesn't grok NULL argument */return;}

A. cpp is as follows:

#include "unp.h"#include<iostream>#include<algorithm>#include<string>#include<cstdlib>using namespace std;int main(int argc, char **argv){int sockfd, n;char recvline[MAXLINE + 1];struct sockaddr_in servaddr;if (argc != 2) {//cout << "ni mei can shu shao le!" << endl;err_quit("usage: a.out <IPaddress>");}if ( (sockfd = socket(AF_INET, SOCK_STREAM,0)) < 0) {//cout << "Fuck ing life ! " << endl;err_sys("socket error");}bzero(&servaddr, sizeof(servaddr));servaddr.sin_family = AF_INET;servaddr.sin_port =  htons(13);if (inet_pton(AF_INET,argv[1],&servaddr.sin_addr) <= 0) { //cout << "inet_pton error for" <<endl;err_quit("inet_pton error for %s",argv[1]);}if (connect(sockfd,(SA *) &servaddr,sizeof(servaddr)) <0) {/*cout << "connect error"<< endl ;*/err_sys("connect error");}while( (n = read(sockfd, recvline, MAXLINE)) >0 ){recvline[n]=0; if (fputs(recvline,stdout) == EOF) {//cout << "Fputs error" << endl ;err_sys("fputss error");}}if (n < 0 ) {   //cout << "read error" <<endl;err_sys("read error");}exit(0);//return 0;}

Thanks to the sharing spirit of the Internet, and to the experts who have recorded problems and provided solutions, let me wait for * nix cainiao to make progress.