I don't think we have file descriptors in shell sciprt like we have in perl, c etc.
You can use this to get your requirement done
Note : This logic is specific for 2 files only
Ok, I'm sure this is a total newbie question, but I think I'm in the right place, no?
I'm trying to call a perl module from a cgi script - Mail::Sendmail - and my web host installed the module in a directory that doesn't seem to be accessible, at least not the way I'm trying. But I thought you... (1 Reply)
I am trying to find a way to check the current status of a file. Such as some cron job processes are dependent on the completion of others. if a file is currently being accessed / modified or simply open state I will wait until it is done being processed before attempting the next process on that... (3 Replies)
Hi,
look at the following code:
The client after estabilishing a connection with the server does the following:
if ((peter = fopen(argv, "r")) == NULL){
printf("errore\n");
exit(0);
}
... (11 Replies)
I have a requirement to close all the file descriptors from 3 to 1024 for a particular application.
Right now, this is how I do it ..
for ( int i = 3 ; i <= 1024; ++i )
close(i);
The change I am looking at is, I want to do away with the number 1024 and replace it with a constant which... (4 Replies)
I am trying to right a function which uses a file descriptor to write to a log file. The problem is that the on the print statement the file descriptor is called bad. Now when I first open the file and print to it in the f_open function by passing the descriptor to f_print_log all works well,... (6 Replies)
Hello All,
Im opening a file desciptor in perl and sending data using print CMD "$xyz".
is there a limit to the length of the string that I can give to this CMD at a time. (3 Replies)
I am trying to use one global declaration --> "exec 2>$ERR" to capture all stderr outputs that may occur anywhere in my script.
Then close it at the end of the script using --> "exec 2<&-"
I am using KSH on Solaris 8.
KSH Version M-11/16/88i
If I comment two "exec .." statements in the... (11 Replies)
hello,
Someone can help me with redirectors?
I am writing this script in bash enviroment on Fedora:
exec 4<> /dev/tcp/10.10.11.30/5000 #open socket in input/output
strings<&4 >file.txt &
I send file descriptor 4 to string command to purge data stream from special char while come from... (3 Replies)
Discussion started by: rattoeur
3 Replies
LEARN ABOUT DEBIAN
io_canread
io_canread(3) Library Functions Manual io_canread(3)NAME
io_canread - return a file descriptor that can be read from
SYNTAX
#include <io.h>
int64 io_canread();
DESCRIPTION
io_canread returns the next file descriptor that can be read from. You have to have used io_wantread() on the file descriptor earlier, and
you have to have called io_wait() or io_waituntil().
These functions then keep an internal data structure on which descriptors were reported readable by the operating system.
Please note that there is no guarantee that there still is data that can be read from the descriptor, just that there was data when
io_wait() or io_waituntil() were called. Another process could have read the data before you. Look at the result from io_tryread().
If there are no more descriptors that you can write to without blocking, io_canwrite will return -1. In this case you should call
io_wait() or io_waituntil() again.
You should use io_tryread(3) to read from the descriptor, not plain read(2). If you use read(2) and you get EAGAIN, call io_eagain(3).
SEE ALSO io_wait(3), io_canwrite(3), io_eagain(3)io_canread(3)