With respect to RudiC, use of a file's access time can be problematic if any other process reads the file, such as backups.
Why 3 programs? Are they three instances of the same program?
If the expense of starting a new process is not onerous, perhaps it would be easier just to use a dispatcher that launches no more than N of your programs:
(pseudo shell code!)
Or the dispatcher could write a file to one of N named-pipes, one for each fileomatic, something like:
(more pseudo shell code)
The idea is that the fileomatic will touch the 'ready' file when it can process a file
Last edited by derekludwig; 11-27-2014 at 02:59 PM..
Reason: Typo in arithmantic expression, and some bad logic
hello...
thats a great forum btw :)
my problem is that I need a list of the Base Level Filesets (BLF) which are needed by a specific program.
Is there any command/tool which shows me that?
during the installation I can choose "Preview only" so that I can see what BLF´s are missing etc but... (4 Replies)
Hi,
I'm new to unix,I wanna know how can I compare timestamp of a file with its touched version.i.e I want to be sure if the touch command has worked properly i.e if the file has been touched then a msg should be printed saying success else failure.All this to be incurred in a script.
Any... (2 Replies)
Hi all,
I'm running a simulator and I'm noticing an slow increase in memory for long simulations such that the simulation has to end because of a lack of memory. A colleague of mine ran Valgrind memcheck and reported that nothing of interest was reported other than known mem leaks. My advisor... (2 Replies)
I will be taking a UNIX course as a part of my college Data Com concentration curriculum. Just thought it would be a good idea to get a little head start, since this class will most likely be quite difficult for someone like me. I never did any programming and I never dealt with Unix or Linux short... (3 Replies)
Hello
Would you tell me how to find which program that update a specific file?
I am implementing migration project.
My machines OS are AIX.
It is because lack of documentation, some program cannot working properly on new machine.
We found the root cause of this problem is that some data... (4 Replies)
Hi
This is my first post and I'm just a beginner. So please be nice to me.
I have a couple of html files where a pattern beginning with "http://www.site.com" and ending with "/resource.dat" is present on every 241st line. How do I extract this to a new text file?
I have tried sed -n 241,241p... (13 Replies)
Hi All,
Your help on the below requirement is highly appreciated.
I am building a program which should pick the file from a source directory and place them into target directory. While selecting the file in source it should look for some pattern in the file name.
Ex:
File Name 1:... (10 Replies)
I have been running a program mseed2sac using the following command
cd IV
find . -type f -exec /swadmin/mseed2sac '{}' \;
The problem is that I end up with a lot of files in directory IV.
Instead I would like to select the designator HHZ, create a
directory IV.SAC and all the files output... (11 Replies)
I know that Qt exists on this IMX6+ the device has Linux 4.9.184 embedded. I need to figure out which version of Qt it has. What is the best way to find a program given only a text based terminal? Is there a way I can grep for it? (2 Replies)
Discussion started by: Circuits
2 Replies
LEARN ABOUT DEBIAN
io_tryread
io_tryread(3) Library Functions Manual io_tryread(3)NAME
io_tryread - read from a descriptor without blocking
SYNTAX
#include <io.h>
int io_tryread(int64 fd,char* buf,int64 len);
DESCRIPTION
io_tryread tries to read len bytes of data from descriptor fd into buf[0], buf[1], ..., buf[len-1]. (The effects are undefined if len is 0
or smaller.) There are several possible results:
o o_tryread returns an integer between 1 and len: This number of bytes was available for immediate reading; the bytes were read into the
beginning of buf. Note that this number can be, and often is, smaller than len; you must not assume that io_tryread always succeeds in
reading exactly len bytes.
o io_tryread returns 0: No bytes were read, because the descriptor is at end of file. For example, this descriptor has reached the end of
a disk file, or is reading an empty pipe that has been closed by all writers.
o io_tryread returns -1, setting errno to EAGAIN: No bytes were read, because the descriptor is not ready. For example, the descriptor is
reading an empty pipe that could still be written to.
o io_tryread returns -3, setting errno to something other than EAGAIN: No bytes were read, because the read attempt encountered a persis-
tent error, such as a serious disk failure (EIO), an unreachable network (ENETUNREACH), or an invalid descriptor number (EBADF).
io_tryread does not pause waiting for a descriptor that is not ready. If you want to pause, use io_waitread or io_wait.
You can make io_tryread faster and more efficient by making the socket non-blocking with io_nonblock().
SEE ALSO io_nonblock(3), io_waitread(3), io_tryreadtimeout(3)io_tryread(3)