Boa Unable To Dup2 The Error Log Bad File Descriptor
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subject ] dup bad file descriptor [ author ] Hello, boa-0.94.14rc17 cannot write my error log: [13/Aug/2003:03:14:11 +0000] log.c:70 (open_logs) - unable to dup2 the error
Grep Standard Input Bad File Descriptor
log: Bad file descriptor /var/log/error_log is a file in ramfs and this has always worked.. until now. How can I fix this? Thanks for your help, Uwe Previous message: [uClinux-dev] XIP Next message: [uClinux-dev] blackfin ? Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] More information about the uClinux-dev mailing list
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Bash Bad File Descriptor
and policies of this site About Us Learn more about Stack Overflow dup2 bad file descriptor c the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags cat standard output bad file descriptor Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only http://mailman.uclinux.org/pipermail/uclinux-dev/2003-August/020399.html takes a minute: Sign up dup2 bad file descriptor up vote 0 down vote favorite I am trying to implement pipe to my shell. Right now it can handle normal commands like ls, who, date etc.. By reading a lot and going in to other stack overflow posts to check how pipe is supposed to work i have come up http://stackoverflow.com/questions/34009794/dup2-bad-file-descriptor with this code that i will demonstrate for you guys. The function basically takes in a command that is should process. void runCommand(Command *cmd){ char **pl = cmd->pgm->pgmlist; int status; Pgm *p = cmd->pgm; //Count the number of pipes and create the right number of filedescriptors int numPipes = countPipes(cmd->pgm); int pipefds[2*numPipes]; //Pipe the file descriptors here and check if there was an error. for(int i = 0; i < (numPipes); i++){ if(pipe(pipefds + i*2) < 0) { perror("couldn't pipe"); exit(EXIT_FAILURE); } } pid_t pid, wpid; int fdr; int fd; int j = 0; while(p != NULL) { pid = fork(); if (pid == 0) { // Child process if (cmd->bakground == 1) // Check if it should be running in the background, if so, assign a new PID { setpgid(pid, 0); } // Check if RSTDOUT is on or not if(cmd->rstdout != NULL){ fd = open(cmd->rstdout, O_WRONLY | O_CREAT | O_TRUNC , S_IRUSR | S_IRGRP | S_IWGRP | S_IWUSR); //fclose(fopen(cmd->rstdout, "w")); printf("in first\n"); dup2(fd,1); close(fd); } // Check if RSTIN is on or not if(cmd->rstdin != NULL) { fdr
uclinux arm s3c4510b process Being ported to Boa-0.94.13 uclinux, a few notes to share with you. Compile a linux c system, including morphology and syntax analysis module for Linux on bison and flex. yacc is a grammar parser generator bison that is the GNU version of yacc and lex and yacc are http://m.blog.csdn.net/article/details?id=51193321 tools used to construct the lexical analyzer and syntax interpreter, Lex and Yacc, you can easily construct a grammar explanations. 1 Extract the Boa-0.94.13.tar.gz, into the boa-0.94.13/src Catalog 2 .. / configure Enter http://m.blog.chinaunix.net/uid-30510400-id-5386094.html generate Makefile Began to make a Error 1: debian :/ home/a/boa-0.94.13/src # make yacc-d boa_grammar.y make: yacc: Command not found make: *** [y.tab.c] Error 127 Solution: debian :/ home/a/boa-0.94.13/src # apt-get install bad file bison Error 2: debian :/ home/a/boa-0.94.13/src # make lex boa_lexer.l to make: lex: Command not found make: *** [lex.yy.c] Error 127 Solution: debian :/ home/a/boa-0.94.13/src # apt-get install flex Error 3: debian :/ home/a/sss/boa-0.94.13/src # make gcc-g-O2-pipe-Wall-I.-c-o util.o util.c util.c: 100:1: error: pasting "t" and "->" does not give a valid preprocessing token make: *** [util.o] Error 1 Solution: Modify the src / compat.h Find # bad file descriptor Define TIMEZONE_OFFSET (foo) foo # # -> tm_gmtoff Modified # Define TIMEZONE_OFFSET (foo) (foo) -> tm_gmtoff Then debian :/ home/a/sss/boa-0.94.13/src # make clean debian :/ home/a/sss/boa-0.94.13/src # make But there is a warning: request.c: In funtion 'get_request': request.c: 84: warning: pointer targets in passing argument 3 of 'accept' differ in signedness Looked unhappy, it does not matter To 84 look request.c. int accept (int socket, struct sockaddr * address, size_t * address_len) prototype. Where the parameter type is wrong. Int to size_t on it. debian :/ home/a/sss/boa-0.94.13/src # make Basically there is no problem. However, when running boa, running, ps this process Solution: Written off if (setuid (0)! = -1) { DIE ("icky Linux kernel bug!"); } Can be a recompile. Generated boa tested on a PC no problem -------------------------------------------------- -------------------- This is at the forum to share, I just started testing have not encountered .... hope to be useful (2) modify the src / log.c Comment out if (dup2 (error_log, STDERR_FILENO) == -1) { DIE ("unable to dup2 the error log"); } As follows: Otherwise, an error occurs: log.c: 73 unable to dup2 the error log: bad file descriptor (3) modify the src / boa.
我所用的环境是在ubuntu12下，交叉编译工具arm-none-linux-gnueabi-gcc（arm-linux-gcc-4.4.3.tar.gz），运行板子安卓手机（最好是烧的android debug版，这样有root权限操作较为方便一些）； 结合网上一些教程结合自己的移植过程中遇到的问题，贴出来；编译之前需要安装bison和flex，这两个工具用，sudo apt-get install就可以安装了； 1．下载Boa源码 下载地址: http://www.boa.org/ 最新发行版本： 0.94.13 下载 boa-0.94.13.tar.gz 解压：# tar xzf boa-0.94.13.tar.gz 2.修改一些头文件 (1)修改 src/compat.h 找到 #define TIMEZONE_OFFSET(foo) foo##->tm_gmtoff修改成#define TIMEZONE_OFFSET(foo) (foo)->tm_gmtoff 否则会出现错误： util.c:100:1: error: pasting "t" and "->" does not give a valid preprocessing token make: *** [util.o] 错误 1 (2)修改 src/log.c 注释掉 if (dup2(error_log, STDERR_FILENO) == -1) { DIE("unable to dup2 the error log"); } 为： /*if (dup2(error_log, STDERR_FILENO) == -1) { DIE("unable to dup2 the error log"); }*/ 否则会出现错误： log.c:73 unable to dup2 the error log:bad file descriptor (3)修改src/boa.c 注释掉下面两句话： if (passwdbuf == NULL) { DIE(”getpwuid”); } if (initgroups(passwdbuf->pw_name, passwdbuf->pw_gid) == -1) { DIE(”initgroups”); } 为 #if 0 if (passwdbuf == NULL) { DIE(”getpwuid”); } if (initgroups(passwdbuf->pw_name, passwdbuf->pw_gid) == -1) { DIE(”initgroups”); } #endif 否则会出现错误：boa.c:211 - getpwuid: No such file or directory 注释掉下面语句： if (setuid(0) != -1) { DIE(”icky Linux kernel bug!”); } 为 #if 0 if (setuid(0) != -1) { DIE(”icky Linux kernel bug!”); } #endif 否则会出现问题：boa.c:228 - icky Linux kernel bug!: No such file or directory 3、生成Makefile文件 执行： #cd boa-0.94.13/src #./configure 4、修改Makefile 在 boa-0.94.13/src目录下修改Makefile vim Makefile 找到CC，CPP，并添加AR，LD，STRIP，如下 CC = arm-none-linux-gnueabi-gcc CPP = arm-none-linux-gnueabi-gcc -E AR = arm-none-linux-gnueabi-ar LD = arm-none-linux-gnueabi-ld STRIP = arm-none-linux-gnueabi-strip 找到生成boa和boa_ind