stdin

We know that stdin is, by default, a buffered input; the proof of that is in usage of any of the mechanisms that "leave data" on stdin , such as scanf() : int main() { char c[10] = {'\0'}; scanf("%9s", c); printf("%s, and left is: %d\n", c, getchar()); return 0; } ./a.out hello hello, and left is 10 10 being newline of course... I've always been curious, is there any way to "peek" at the stdin buffer without removing whatever may reside there? EDIT A better example might be: scanf("%9[^.]", c); With an input of "at.ct", now I have "data" ( ct\n ) left on stdin , not just a newline. Portably,

With C++ how do i launch an exe/process with stdin stdout and stderr? I know how to do this in .NET and i remember using popen in the past but popen seems to allow stdin OR stdout not both and not all 3. I need this for windows but a linux solution is welcome as i'll need it for the same project in the future. You shoud use CreateProcess from WinApi. It takes as argument an object of struct STARTUP_INFO type. You can set hStdin, hStdout, and hStderr fields of the object to redirect those streams of child process to file handles you want (file, pipe, socket...) MSalters A portable solution

I want to read a single character at-a-time from the command line in PHP, however it seems as though there is some kind of input buffering from somewhere preventing this. Consider this code: #!/usr/bin/php <?php echo "input# "; while ($c = fread(STDIN, 1)) { echo "Read from STDIN: " . $c . "\ninput# "; } ?> Typing in "foo" as the input (and pressing enter), the output I am getting is: input# foo Read from STDIN: f input# Read from STDIN: o input# Read from STDIN: o input# Read from STDIN: input# The output I am expecting is: input# f input# Read from STDIN: f input# o input# Read from STDIN: o

Is it possible to listen for incoming keystrokes in a running nodejs script? If I use process.openStdin() and listen to its 'data' event then the input is buffered until the next newline, like so: // stdin_test.js var stdin = process.openStdin(); stdin.on('data', function(chunk) { console.log("Got chunk: " + chunk); }); Running this, I get: $ node stdin_test.js <-- type '1' <-- type '2' <-- hit enter Got chunk: 12 What I'd like is to see: $ node stdin_test.js <-- type '1' (without hitting enter yet) Got chunk: 1 I'm looking for a nodejs equivalent to, e.g., getc in ruby Is this possible? You

Is there a way to effectively do this in bash: /my/bash/script < echo 'This string will be sent to stdin.' I'm aware that I could pipe the output from the echo such as this: echo 'This string will be piped to stdin.' | /my/bash/script You can use one-line heredoc cat <<< "This is coming from the stdin" the above is the same as cat <<EOF This is coming from the stdin EOF or you can redirect output from a command, like diff <(ls /bin) <(ls /usr/bin) or you can read as while read line do echo =$line= done < some_file or simply echo something | read param You were close /my/bash/script <<< 'This

I can't seem to figure out what's wrong with this code: #include <stdio.h> #include <ctype.h> #include <string.h> #include <stdlib.h> #define MAX 100 #define TRUE 1 #define FALSE 0 char sect_cat; char customer_name[MAX]; char customer_number[MAX]; /* error handling is easier */ int prev_unit = 0; int current_unit = 0; int consumed = 0; int set = FALSE; float init_bill; float tax; float total_bill; void get_userinfo() { printf("Enter sector category: "); scanf("%c", &sect_cat); printf("Enter customer name: "); fflush(stdin); scanf("%sn", &customer_name); set = FALSE; while (set == FALSE) {