I don't know if it is legal on SOF to access such a specific question, but here I go:
I've found this wonderful piece of code which takes all the samples from a WAV file and passes it into an array.
The code compiles, but I can't seem to figure out where to pass the argument of where the file is and what its name is.
Any help?
PS If this code does what it says it does, I think it could be useful to a lot of people.
Thanks!
If you look at the code it's reading from stdin (and it even says in the description above the code: "It reads from stdin"). Evidently it's designed to be used as a command line tool (or "filter") which can be piped with other tools, or standalone using I/O redirection.
You should be able to pipe output from wget or curl.
wget -O - http://www.whatever.com/somefile.wav | yourpieceofcode
Related
This is related to u-boot.
I looked at this link (How to test the return of a command in U-Boot CLI) but it doesn't cover what I need. I also checked some other pages related to the 'test' command in u-boot but I can't figure out how to do what I would like. So there it is.
I have a u-boot command on a SBC which returns a set of information as text printed on the screen, where some part are strings representing versions. What I would like is to check whether the command return contains some specific strings to choose automatically what to do.
I have seen a few 'test' command help, but I couldn't figure out how to do this type of check on the text returned by this command. My goal is to have a set of nested ifs to choose in the different cases, or anything equivalent. If regex can be used, they perhaps could be helpful.
Does anybody know how to do this?
Thank you.
In U-Boot's hush shell there is no support for pipes. There is also no command like grep. So there are no means to succeed via U-Boot's built-in shell commands.
If you have access to the source of the command that you are executing, you could change it and use function env_set() to write the relevant data to environment variables and then use test for your purposes.
So for some reason when I run my script and have it output to the terminal just as it would, I get my intended output. Yet when I redirect the output to a file, I don't receive full output.
Let's say I have an executable named "filename" and run it "./filename", the output on the terminal is, let's say :
a
b
c
Yet if I do "./filename > output.txt" or "./filename |& tee output.txt", the output on the terminal AND the output.txt text file is just, let's say:
a
b
I know this isn't very specific, but my output is huge. I was thinking this would be general enough to provide general solutions/ possible problems.
I'm using a program someone else made, so I don't know where this additional output is called. Yet, it shouldn't matter since the functionality of the program doesn't change, just what's being output.
Without a minimal code sample to reproduce, it's very hard to guess what's going on.
But some things you could try:
Redirect all output streams to your file, i.e. your-script &> output.txt
Run it through strace and look for write and open calls to see what's going on
Read and debug the source code to figure out what's going on
Hello I am currently trying to printf a certain part of the command line when i run my program. I currently run my program as follows
zcat gcc | sim
What i am trying to accomplish is print out to a seperate file the 'gcc' part of the command line. Is there any way to accomplish this. Thanks for the help
I forgot to mention this is in c not C++
The 'sim' program only knows that it has data from stdin. It doesn't know what is handing the data to stdin - it may be another program, or redirected input, or from a device.
From 'sim' POV, there's only data from stdin.
IF you can guarantee that you will always receive data from another process via a pipe, you can start looking for process headers matching the 'sim' process, and from then extracting process info from associated processes. However, I suspect that this is more than you're willing to go.
You are passing output of zcat (through pipe) to your program, it doesn't know details of arguments passed to zcat.
You can explicitly pass it as a part of input stream though,
(echo 'zcat gcc'; zcat gcc ) | sim
but that is a hack. It may be Ok if you are planning to run your
program this way only.
I want to know what system call is used in linux C programming is used to know whether a file is modified.
I know that make utility compiles the file using the modification dates only.
I want know how to find whether the file is modified or not.
Thanks in advance
Using md5sum or sha1sum will hash the contents of the file, which should give you a better indication of actual changes than modification dates.
stat(2) gives you file times and more.
Edit 0:
You can look into fcntl(2) and F_NOTIFY flag - you'd have to open the directory, not the file itself though. Or the newer Linux inotify(7) facility.
You can use ls and various flags on it, like -l or -t and pipe to grep or something. That will tell you when the last file was modified. But it doesn't really tell you if the file was modified. I think the only real way you can know that is if you are keeping track of when the last time it was modified in general (like checking from backups or something).
Basically I want to do a program almost like a keylogger. The thing is that I as network admin sometimes I don't remember what I did to a machine on certain case, or same times I make howto's and tutorials for linux. I want to record what have i done.
So basically the idea of this program is:
you type the name of the program, (I call it rat for the moment)
$ rat
Welcome everything from now on will be recorded
recording $ ls
file1 file2 file3
recording $ quit
Bye bye
Everything you do will go out to an xml file. Something like this
<?xml version='1.0' encoding='UTF-8' ?>
<rat>
<command>
<input>ls</input>
<output>file1 file2 file3</output>
<err><err>
</command>
</rat>
i am doing some tests with fp_in = popen( input, "w");
and system, but first with popen i cant change directories and with "system i cant properly manage the input and output.
I was also checking if there is something I can do to bash like a plugin but haven't find any information.
At some points if feels like it I should create another shell (which is way beyond my current abilities) or fork bash sh. But it should been that complicated right.
I am open to suggestion where to start.
I am rusty with C, so I am reading again a lot of basic stuff.
With the xml file, later i was thinking on making a program to store this data and/or editing this data so i can create tutials and howto.
I can think of many ways of expanding this up to using printscreen so all the stored images go to a file you can upload to a server (for the moment i am glad to store the data). It could be a usefull tool.
ps. I do know this can be use for evil things too.
There already exists the script command, which will record all input and output into the terminal, writing it into a transcript. I would recommend just using that, unless you have particular needs that it doesn't meet. Actually, the nicest version of script that I've seen has been the NetBSD version, so you may want to look into that if the Linux version doesn't meet your needs.
If you would like to write it yourself, instead of using system, I would recommend that you use fork/exec to create a single shell process, which you copy all input and output into. To get an idea of how this works, I'd recommend looking at the source code for an existing version of script.
Most shells have a script built-in which will simply record the text in- and out- from the command line. Not quite what you're looking for... To my surprise script is not a built in, which means it is a model for building what you want.
The script command does almost what you want: it simply records the text in- and out- from the command line.
If you make your prompt distinctive (so that you can reliably tell the difference between shell commands and everything else) you can post-process the output of script to achieve your goals. Alternately you can hack script to get it to emit the XML you're looking for.
You can also try approaching this from a different angle. Instead of using a regular shell, connect to the machine using ssh or telnet and run your commands that way. Many ssh/telnet clients (PuTTY, for instance) have an option to log all console input and output during the session. You should be able to post-process this log to generate whatever type of logfile that you need.
Depending on your setup, you might not even have to use a second machine (you should be able to ssh into yourself).