stdin

问题 I am having this problem when I am trying to copy to AWS redshift. This is the code I am trying to run: with open('path/to/files, 'rb') as fo: cursor.copy_from(fo, 'schema.table', sep=',') cursor.commit() And I encountered the error: psycopg2.ProgrammingError: syntax error at or near "stdin" LINE 1: ...Y schema.table FROM stdin WITH... I am running python 3.5 with psycopg2. Hope that you guys can help! Thx in advance! 回答1: AWS Redshift is not PostgreSQL, though it supports a subset of

问题 I have compiled the following code with gcc int main() { int a = 0; fprintf( stdin, "%d", 123 ); fscanf( stdin, "%d", &a ); printf( "%d\n", a ); return 0; } In my expectation, the program should executes straightly (i.e., the program never pause and wait for user input). But it still stop, and wait for my input. I want to know what happen when I try to write something to stdin and how to modify this code and it can execute straightly? 回答1: stdin is for input only, stdout is for output.

问题 Consider the following perl script ( read.pl ): my $line = <STDIN>; print "Perl read: $line"; print "And here's what cat gets: ", `cat -`; If this script is executed from the command line, it will get the first line of input, while cat gets everything else until the end of input ( ^D is pressed). However, things are different when the input is piped from another process or read from a file: $ echo "foo\nbar" | ./read.pl Perl read: foo And here's what cat gets: Perl seems to greadily buffer

问题 I'm trying to learn erlang through interviewstreet. I just learning the language now so I know almost nothing. I was wondering how to read from stdin and write to stdout. I want to write a simple program which writes "Hello World!" the number of times received in stdin. So with stdin input: 6 Write to stdout: Hello World! Hello World! Hello World! Hello World! Hello World! Hello World! Ideally I will read the stdin one line at a time (even though it's just one digit in this case) so I think I

问题 I'm writing a program that reads multiple URLs (one per line) from standard input, slightly adapts them and makes HTTP requests for each of those multiple URLs in parallel. Responses are printed to standard output. Here's the code: {-# LANGUAGE OverloadedStrings #-} module Main where import Control.Monad import Network.Wreq import Control.Concurrent.MSem import Control.Concurrent.Async import Control.Concurrent (threadDelay) import qualified Data.Traversable as T main :: IO () main = void $

问题 I want to test some (python 3) code that directly uses the print and input functions. As I understand it, the easiest way to do this is by dependency injection: modifying the code so that it takes input and output streams as arguments, using sys.stdin and sys.stdout by default and passing in mock objects during testing. It's obvious what to do with print calls: print(text) #replaced with... print(text, file=output_stream) However, input doesn't have arguments for input and output streams.

问题 I want to test some (python 3) code that directly uses the print and input functions. As I understand it, the easiest way to do this is by dependency injection: modifying the code so that it takes input and output streams as arguments, using sys.stdin and sys.stdout by default and passing in mock objects during testing. It's obvious what to do with print calls: print(text) #replaced with... print(text, file=output_stream) However, input doesn't have arguments for input and output streams.

问题 I have a socket server in Node.js and I'd like to be able to read from stdin at the same time the server is listening. It works only partially. I'm using this code: process.stdin.on('data', function(chunk) { for(var i = 0; i < streams.length; i++) { // code that sends the data of stdin to all clients } }); // ... // (Listening code which responds to messages from clients) When I don't type anything, the server responds to messages of the clients, but when I start typing something, it isn't

问题 Here I'm trying to get an user input with getline . Upon receiving an interrupt ^C I want it to signal getline to stop and resume with my program instead of terminating it. I tried to write a newline to stdin but apparently that doesn't work. fwrite("\n", 1, 1, stdin); So what would be a way to achieve this? 回答1: Assuming your code resembles this: int main(int argc, char **argv) { //Code here (point A) getline(lineptr, size, fpt); //More code here (point B) } Include <signal.h> and bind

问题 I am having a problem with the Enter key or character in the stdin stream messing up following input calls. let's say I have one input call, so I enter in the stuff. but then takes the Enter key as input for the next input call. I think in c++ there is cin.ignore() to do the trick. I just can't find the C version. The input methods are getchar() and gets() . Sorry if this is a duplicate. I couldn't find the question that matches mine. thanks for any help! printf("Do you want to view the lines