Sponsored Content
Full Discussion: How to skip getchar in C?
Top Forums Programming How to skip getchar in C? Post 302459425 by cprogdude on Monday 4th of October 2010 03:59:05 PM
Old 10-04-2010
Quote:
Originally Posted by Corona688
You can't do this with getchar(), you'll have to use read() instead. More details in a bit.

---------- Post updated at 03:31 PM ---------- Previous update was at 03:19 PM ----------

This should timeout at 5 seconds. The timeout happens in the terminal itself.

Code:
#include <stdio.h>
#include <unistd.h>

int main(void)
{
        int c;
        // Save sane TTY settings
        system("stty -g > ~/.stty-save");
        // Set TTY timeout of 50 tenths of a second, minimum read size 0
        system("stty -icanon min 0 time 50");

        while(read(STDIN_FILENO, &c, 1) == 1)
        {
                fprintf(stderr, "read 1 bytes\n");
        }

        // Restore sane tty settings
        system("stty $(cat ~/.stty-save)");
        return(0);
}


Thanks man. I use "select" it works but the problem is I'm unable to flush my input stream. How do I do that?
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

getchar()

hey everyone! got another problem here. how would i use the getchar() in a prompt: Press any key to continue the way i did it was to define a char variable named ch and then wrotechar ch ... ch = getchar(); printf("Press any key to continue"); getchar():if you press enter it exits, but... (2 Replies)
Discussion started by: primal
2 Replies

2. BSD

FreeBSD skip UserConfig...

When I boot FreeBSD from cd/floppy, it skips the UserConfig program. I have no idea why! And if I skip this step, my hardware won't work. ( I already tried...) Can anyone help me with this??? (2 Replies)
Discussion started by: Enoch Chan
2 Replies

3. Shell Programming and Scripting

Skip new line

Hi, how can I skip the new line of echo? In SH!!!! echo "the date is :" date and result I want is the date is : Tue Oct 11 22:24:37 WEST 2005 I've already tried including the \c inside the echo, but it didn't work. Thanks! (2 Replies)
Discussion started by: pmpx
2 Replies

4. Shell Programming and Scripting

Bash replacement to getchar

There's a replacement in bash for getchar or get functions of C and C++?Those functions read the next char avaliable in the input stream. I've tried something like: OLD_STTY=`stty -g` stty cbreak -echo look=`dd if=/dev/tty bs=1 count=1 2>/dev/null` stty $OLD_STTY But it is not working... (3 Replies)
Discussion started by: Asafe
3 Replies

5. Shell Programming and Scripting

go to / skip in script

Hi all I have some script like this #!/bin/bash mv /tmp/file1 tmp/file2 if ] ; then cp /tmp/filetest/ tmp/file3 if ] then echo "succes" else echo "failed" fi else echo "failed" fi i didn't try to see if it's work, the thing is that i don't care if... (4 Replies)
Discussion started by: naamas03
4 Replies

6. Programming

Help on getchar

I wanted to make a simple program that writes chracters in a file but i didnt want to press enter .So i found the getchar which doesnt need enter.If i pass (int) getchar to putc ,in the file it shows a P character.The (int) getchar says it is equal to1734747216 so i do (int) getchar-1734747216... (4 Replies)
Discussion started by: fireblast
4 Replies

7. Programming

How to kill disowned process which calls getchar() in code

Hi, What happens to process state when getchar() is called? I wrote a C code in which I call getchar() somewhere down the road. I forgot about that, I started the process, put it in bg and disowned it using "disown". Now, how do I see where that process has gone/how do kill it? Thanks, Amrut (1 Reply)
Discussion started by: 17amrut29
1 Replies

8. UNIX for Advanced & Expert Users

Skip files in use

Hi all, i'm trying to configure a script that will find and gzip the searched files, this is easy enough, find /var/log/myfolder/*.log -type f -mtime +1 -exec gzip {} \; cd /var/log/myfolder/ mv *gz myzipped_folder/ but what it would be very handy is to skip the files in use,because tomcat... (13 Replies)
Discussion started by: charli1
13 Replies

9. Programming

What is the difference between printf and putchar() or scanf and getchar() ?

Im a newbie to programming language, i found tat there r these function called printf and putchar() as well as scanf and getchar(), im curious abt why do dey hav these 2 different function although dey r doing the same instruction? :confused: (13 Replies)
Discussion started by: kris26
13 Replies

10. Shell Programming and Scripting

Skip first and last line

Hi All I have a sample file like below: 012312112 1372422843 1236712 1372422843 1275127 3109301010 from which I wan't to: 1.)delete... (10 Replies)
Discussion started by: swasid
10 Replies
STTY(1) 							   User Commands							   STTY(1)

NAME
stty - change and print terminal line settings SYNOPSIS
stty [-F DEVICE | --file=DEVICE] [SETTING]... stty [-F DEVICE | --file=DEVICE] [-a|--all] stty [-F DEVICE | --file=DEVICE] [-g|--save] DESCRIPTION
Print or change terminal characteristics. -a, --all print all current settings in human-readable form -g, --save print all current settings in a stty-readable form -F, --file=DEVICE open and use the specified DEVICE instead of stdin --help display this help and exit --version output version information and exit Optional - before SETTING indicates negation. An * marks non-POSIX settings. The underlying system defines which settings are available. Special characters: * dsusp CHAR CHAR will send a terminal stop signal once input flushed eof CHAR CHAR will send an end of file (terminate the input) eol CHAR CHAR will end the line * eol2 CHAR alternate CHAR for ending the line erase CHAR CHAR will erase the last character typed intr CHAR CHAR will send an interrupt signal kill CHAR CHAR will erase the current line * lnext CHAR CHAR will enter the next character quoted quit CHAR CHAR will send a quit signal * rprnt CHAR CHAR will redraw the current line start CHAR CHAR will restart the output after stopping it stop CHAR CHAR will stop the output susp CHAR CHAR will send a terminal stop signal * swtch CHAR CHAR will switch to a different shell layer * werase CHAR CHAR will erase the last word typed Special settings: N set the input and output speeds to N bauds * cols N tell the kernel that the terminal has N columns * columns N same as cols N ispeed N set the input speed to N * line N use line discipline N min N with -icanon, set N characters minimum for a completed read ospeed N set the output speed to N * rows N tell the kernel that the terminal has N rows * size print the number of rows and columns according to the kernel speed print the terminal speed time N with -icanon, set read timeout of N tenths of a second Control settings: [-]clocal disable modem control signals [-]cread allow input to be received * [-]crtscts enable RTS/CTS handshaking csN set character size to N bits, N in [5..8] [-]cstopb use two stop bits per character (one with `-') [-]hup send a hangup signal when the last process closes the tty [-]hupcl same as [-]hup [-]parenb generate parity bit in output and expect parity bit in input [-]parodd set odd parity (even with `-') Input settings: [-]brkint breaks cause an interrupt signal [-]icrnl translate carriage return to newline [-]ignbrk ignore break characters [-]igncr ignore carriage return [-]ignpar ignore characters with parity errors * [-]imaxbel beep and do not flush a full input buffer on a character [-]inlcr translate newline to carriage return [-]inpck enable input parity checking [-]istrip clear high (8th) bit of input characters * [-]iutf8 assume input characters are UTF-8 encoded * [-]iuclc translate uppercase characters to lowercase * [-]ixany let any character restart output, not only start character [-]ixoff enable sending of start/stop characters [-]ixon enable XON/XOFF flow control [-]parmrk mark parity errors (with a 255-0-character sequence) [-]tandem same as [-]ixoff Output settings: * bsN backspace delay style, N in [0..1] * crN carriage return delay style, N in [0..3] * ffN form feed delay style, N in [0..1] * nlN newline delay style, N in [0..1] * [-]ocrnl translate carriage return to newline * [-]ofdel use delete characters for fill instead of null characters * [-]ofill use fill (padding) characters instead of timing for delays * [-]olcuc translate lowercase characters to uppercase * [-]onlcr translate newline to carriage return-newline * [-]onlret newline performs a carriage return * [-]onocr do not print carriage returns in the first column [-]opost postprocess output * tabN horizontal tab delay style, N in [0..3] * tabs same as tab0 * -tabs same as tab3 * vtN vertical tab delay style, N in [0..1] Local settings: [-]crterase echo erase characters as backspace-space-backspace * crtkill kill all line by obeying the echoprt and echoe settings * -crtkill kill all line by obeying the echoctl and echok settings * [-]ctlecho echo control characters in hat notation (`^c') [-]echo echo input characters * [-]echoctl same as [-]ctlecho [-]echoe same as [-]crterase [-]echok echo a newline after a kill character * [-]echoke same as [-]crtkill [-]echonl echo newline even if not echoing other characters * [-]echoprt echo erased characters backward, between `' and '/' [-]icanon enable erase, kill, werase, and rprnt special characters [-]iexten enable non-POSIX special characters [-]isig enable interrupt, quit, and suspend special characters [-]noflsh disable flushing after interrupt and quit special characters * [-]prterase same as [-]echoprt * [-]tostop stop background jobs that try to write to the terminal * [-]xcase with icanon, escape with `' for uppercase characters Combination settings: * [-]LCASE same as [-]lcase cbreak same as -icanon -cbreak same as icanon cooked same as brkint ignpar istrip icrnl ixon opost isig icanon, eof and eol characters to their default values -cooked same as raw crt same as echoe echoctl echoke dec same as echoe echoctl echoke -ixany intr ^c erase 0177 kill ^u * [-]decctlq same as [-]ixany ek erase and kill characters to their default values evenp same as parenb -parodd cs7 -evenp same as -parenb cs8 * [-]lcase same as xcase iuclc olcuc litout same as -parenb -istrip -opost cs8 -litout same as parenb istrip opost cs7 nl same as -icrnl -onlcr -nl same as icrnl -inlcr -igncr onlcr -ocrnl -onlret oddp same as parenb parodd cs7 -oddp same as -parenb cs8 [-]parity same as [-]evenp pass8 same as -parenb -istrip cs8 -pass8 same as parenb istrip cs7 raw same as -ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -opost -isig -icanon -xcase min 1 time 0 -raw same as cooked sane same as cread -ignbrk brkint -inlcr -igncr icrnl -iutf8 -ixoff -iuclc -ixany imaxbel opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke, all spe- cial characters to their default values Handle the tty line connected to standard input. Without arguments, prints baud rate, line discipline, and deviations from stty sane. In settings, CHAR is taken literally, or coded as in ^c, 0x37, 0177 or 127; special values ^- or undef used to disable special characters. AUTHOR
Written by David MacKenzie. REPORTING BUGS
Report stty bugs to bug-coreutils@gnu.org GNU coreutils home page: <http://www.gnu.org/software/coreutils/> General help using GNU software: <http://www.gnu.org/gethelp/> COPYRIGHT
Copyright (C) 2009 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO
The full documentation for stty is maintained as a Texinfo manual. If the info and stty programs are properly installed at your site, the command info coreutils 'stty invocation' should give you access to the complete manual. GNU coreutils 7.1 July 2010 STTY(1)
All times are GMT -4. The time now is 03:47 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy