Tricking a Unix Commandline Program into Accepting a File Stream

Posted by Alan Storm on Stack Overflow See other posts from Stack Overflow or by Alan Storm
Published on 2010-03-09T05:43:38Z Indexed on 2010/03/09 5:51 UTC
Read the original article Hit count: 378

Filed under:

unix

|

unix-programming

|

pipes

Hypothetical situation. I have a command line program in *nix (linux, BSD, etc.). It was written so that you pass it a text file as an argument

$ program file.txt

Run the program, it looks at the text in file.txt.

Is it possible to "trick" this program into accepting input from a file stream rather than reading a file via disk? I'm pretty comfortable using unix pipes to do stuff, but there's still something a little mysterious about their internals that make it so I can't say (definitively) yes or not to the above question.

© Stack Overflow or respective owner

Related posts about unix

polkit: disable all users except those in group wheel?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Is it possible to do the following using 1 polkit .pkla file? Disable all users except those in the wheel group from using polkit. The users in the wheel group will need to provide the root password when using polkit. /etc/polkit-1/localauthority/50-local.d/wheel-only.pkla [disable all users… >>> More
How to find other end of unix socket connection?

as seen on Server Fault - Search for 'Server Fault'
I have a process (dbus-daemon) which has many open connection over UNIX sockets. One of these connections is fd #36: =$ ps uw -p 23284 USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND depesz 23284 0.0 0.0 24680 1772 ? Ss 15:25 0:00 /bin/dbus-daemon --fork… >>> More
Meaning of directories on Unix and Unix like systems

as seen on Server Fault - Search for 'Server Fault'
I've been using Linux for a couple of years now but I still haven't figured out what the origin or meaning of some the directory names are on Unix and Unix like systems. E.g. what does etc stand for or var? Where does the opt name come from? And while we're on the topic anyway. Can someone give a… >>> More
Easy understanding of UNIX and UNIX shell scripting!!

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi All, I am beginner to UNIX,UNIX Shell Scripting. Can you please guide me through any excellent sites for unix(which are easy to understand),some study materials(tutorials),video tutorials. Please help!! Thanks! >>> More
Is Mac OS X a licensed Unix or Unix-like clone that conforms to Unix specification?

as seen on Super User - Search for 'Super User'
Is Mac OS X developed on a licensed Unix or is it a Unix-like clone that, unlike Linux, conforms to Unix specification well enough to be registered as a Unix OS. Not until Leopard, Mac OS X did not gain the Unix certification. But in Leopard, Terminal still print: GNU bash, version 3.2.48(1)-release… >>> More

Related posts about unix-programming

How to Practice Unix Programming in C?

as seen on Stack Overflow - Search for 'Stack Overflow'
After five years of professional Java (and to a lesser extent, Python) programming and slowly feeling my CS education slip away, I decided I wanted to broaden my horizons / general usefulness to the world and do something that feels more (to me) like I really have an influence over the machine. I… >>> More
PS Command in Solaris

as seen on Super User - Search for 'Super User'
PS Command output is truncated in solaris. I tried the below command after googling out. It doesn't work. Not sure what needs to be done /usr/ucb/ps awwx >>> More
how can i edit .bashrc file

as seen on Super User - Search for 'Super User'
i am working for cisco. I want to edit that .bashrc file.So can any body suggest what I will do? >>> More
using sed, how to change the text on line seven to read seventh?

as seen on Super User - Search for 'Super User'
using sed, how to change the text on line seven to read seventh? Steve Blenheim:238-923-7366:95 Latham Lane, Easton, PA 83755:11/12/56:20300 Betty Boop:245-836-8357:635 Cutesy Lane, Hollywood, CA 91464:6/23/23:14500 Igor Chevsky:385-375-8395:3567 Populus Place, Caldwell, NJ 23875:6/18/68:23400 Norma… >>> More
Coding exercise for Linux Systems Admin?

as seen on Server Fault - Search for 'Server Fault'
Hello All, I am preparing for a Systems Admin(linux) role for a big company(top 10 companies) and one of the requisite is knowledge of a language like perl, python or Ruby. I have a phone interview which involves sharing a editor with the interviewer, now what kind of coding exercise can I expect… >>> More