pipe

问题 #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> int main( int argc, char **argv) { int pfds[ 2], i; size_t pbytrd; pid_t childpid; char buffer[ 200]; pipe( pfds); if( ( childpid = fork() ) == -1) { perror( "fork error: "); exit( 1); } else if( childpid == 0) { close( pfds[ 0]); dup2( pfds[1], 1); close( pfds[ 1]); for( i = 0; i < 10; i++) printf("Hello..."); execlp( "xterm","xterm","-e","./sample_a", (char *) 0); exit( 0); } else { close( pfds

问题 In Linux (2.6.35-22-generic), man pipe states that pipe() creates a pipe, a unidirectional data channel that can be used for interprocess communication." In FreeBSD (6.3-RELEASE-p5), man pipe states that The pipe() system call creates a pipe, which is an object allowing bidirectional data flow, and allocates a pair of file descriptors." One is unidirectional, the other is bidirectional. I hope this isn't a silly question, but which method is the standard way of doing this? Are they both POSIX

问题 In Linux (2.6.35-22-generic), man pipe states that pipe() creates a pipe, a unidirectional data channel that can be used for interprocess communication." In FreeBSD (6.3-RELEASE-p5), man pipe states that The pipe() system call creates a pipe, which is an object allowing bidirectional data flow, and allocates a pair of file descriptors." One is unidirectional, the other is bidirectional. I hope this isn't a silly question, but which method is the standard way of doing this? Are they both POSIX

问题 This is my try: CMD file: @SET PATH=%PATH%;D:\mingw\bin type test10.cpp | g++ -xc++ -o test10.exe code (irrelevant here): int main() {} error I get: g++: fatal error: no input files compilation terminated. I thought that the -x option is for signalizing stdin input, gcc itself said me that. 回答1: The -x option specifies the input language, but it doesn't tell g++ to read from stdin. To do that, you can pass a single dash as a file name. type test10.cpp | g++ -o test10.exe -x c++ - 来源： https:/

问题 Is there a more concise/standard idiom (e.g., a JDK method) for "piping" an input to an output in Java than the following? public void pipe(Reader in, Writer out) { CharBuffer buf = CharBuffer.allocate(DEFAULT_BUFFER_SIZE); while (in.read(buf) >= 0 ) { out.append(buf.flip()); buf.clear(); } } [EDIT] Please note the Reader and Writer are given . The correct answer will demonstrate how to take in and out and form a pipe (preferably with no more than 1 or 2 method calls). I will accept answers

问题 I would like to call the numberPipe on my custom pipe I find this answer Angular2 use basic pipe in custom pipe but I this solution don't work for me. I have an error "The pipe 'bigInteger' could not be found" import { Pipe, PipeTransform } from "@angular/core" import { CurrencyPipe } from "@angular/common" @Pipe({ name: "bigInteger" }) export class BigInteger extends CurrencyPipe implements PipeTransform { transform(value: any): string { return value } } 回答1: update this should be fixed

问题 I have a long-running console-based application Sender that sends simple text to STDOUT using non-buffered output such as cout << "Message" << flush() . I want to create an MFC dialog-based application (named Receiver ) that starts Sender and can read it's output. Receiver should also be able to detect when Sender has died, or be able to kill Sender if it wants to. Sender knows nothing of Reciever , and I can't change Sender 's code. My first attempt was to create pipes with redirected STDIN

问题 I'm creating a small program which contains three processes; a source process, a filter process and a sink process. The stdout of the source process is redirected to the stdin of the filter process, and the filter process' stdout is redirected to the sink process' stdin. My problem is that no output is printed to stdout from the sink process. Can any of you see the problem in the following tiny snippet of code? #include <unistd.h> #include <stdio.h> #include <stdlib.h> int main(int argc, char

问题 I try to handle some pipes in a CAD Programm with c++. The programm Geograf has two pipes. They are both in the following path: \.\pipe\GGPIPE The interesting on this pipe is, that I have to open a pipe then close a pipe and open a pipe again. After this steps, I can send commands through the pipe to Geograf. My problem or question is, why I can write to pipe the only one time ? After I excecute my program the second time, the handle have a INVALID_HANDLE_VALUE. If I want to send a command

问题 I need to somehow get the output of ispell -l into an array so that I can loop through them.. So far ive got this cat $1 | ispell -l I have tried to read them in line by line into an array but that hasnt worked for me any suggestions? 回答1: Recent bash comes with mapfile or readarray : readarray stuff < <(ispell -l < "$1") echo "number of lines: ${#stuff[@]}" ( this example returns effectively ispell -l < "$1"|wc -l ) beware of the mistake to do e.g. ls | readarray , it won't work because