There is no standard API for returning this information. You need to use the FIONREAD ioctl if it is available on your platform. Typical code would be something like the following.
Code:
#include <sys/ioctl.h>
int chars_avail;
int result;
result = ioctl (tty, FIONREAD, &chars_avail);
Hi,
I have a file that has 300 records with a load of fields. two of them are:
field_1 has between 8-9 bytes i.e. 012345678, 0123456789
field_2 has 10 bytes i.e. 01234567890
I want to be able to echo out the total of each of these fields i.e.
200 (have 8 - 9 bytes)
100 (have 10 bytes)... (3 Replies)
Im using the vmstat command to display the CPU run queue, but i want to put that into a program so is there a way to just display the number under the r?
Thanks, (1 Reply)
Hi,
i have following line in my code.
eport.pl < $4 | dos2ux | head -2000 | paste -sd\| - | awk -v S="$1" '
Issue is, i get a message saying "awk:input line | found /file/path cannot be longer than 3000 bytes."
"source line number is 3"
Can someone help me with this please? (4 Replies)
Hi,
Currently we are experiencing qdaemon died, hourly.
We have more than 10,000 print queue on AIX 5.3.
Would this cause the qdaemon to die?
What is the maximum number of print queue on AIX 5.3?
Thank you in advance. (0 Replies)
1) I need a shell code to count the number of files ( without directories or sub-directories ) in a directory given as arguments I tried this code but it didn't work , maybe I tried the wrong one:
numOfFiles=`find $1 -type f -maxdepth 1 | wc -l`
I found it in another thread in this site..
... (17 Replies)
Guys,
I want to get the high CPU utilization from top.
I am using below code :
top -d2 >> /home/dba_monitoring/host_top_output.txt
echo "Script started `date`" > $runlog
usage=`grep "^ *$1" /home/dba_monitoring/host_top_output.txt | awk '{print $12}' | sed 's/%//'`
And getting below... (7 Replies)
Hi,
I am using the libxml2 sax parser to parse a in memory xml string along with validating it against a schema.
I am using the following code:
xmlSAXHandlerPtr sax_ = new xmlSAXHandler();
sax_->initialized = XML_SAX2_MAGIC;
sax_->startElementNs =... (0 Replies)
I am writing a bash script to find out all the files in a directory which are empty. I am running into multiple issues. I will really appreciate if someone can please help me.
#!/bin/bash
DATE=$(date +%m%d%y)
TIME=$(date +%H%M)
DIR="/home/statsetl/input/civil/test"
... (1 Reply)
Hello guys. I really hope someone will help me with this one..
So, I have to write this script who:
- creates a file home/student/vmdisk of 10 mb
- formats that file to ext3
- mounts that partition to /mnt/partition
- creates a file /mnt/partition/data. In this file, there will... (1 Reply)
hello,
suppose, entered input is of 1-40 bytes, i need it to be converted to 40 bytes exactly.
example: if i have entered my name anywhere between 1-40 i want it to be stored with 40 bytes exactly.
enter your name:
donald duck (this is of 11 bytes)
expected is as below - display 11... (3 Replies)
Discussion started by: shravan.300
3 Replies
LEARN ABOUT REDHAT
read
read(n) Tcl Built-In Commands read(n)
__________________________________________________________________________________________________________________________________________________NAME
read - Read from a channel
SYNOPSIS
read ?-nonewline? channelId
read channelId numChars
_________________________________________________________________DESCRIPTION
In the first form, the read command reads all of the data from channelId up to the end of the file. If the -nonewline switch is specified
then the last character of the file is discarded if it is a newline. In the second form, the extra argument specifies how many characters |
to read. Exactly that many characters will be read and returned, unless there are fewer than numChars left in the file; in this case all |
the remaining characters are returned. If the channel is configured to use a multi-byte encoding, then the number of characters read may |
not be the same as the number of bytes read. |
If channelId is in nonblocking mode, the command may not read as many characters as requested: once all available input has been read, the |
command will return the data that is available rather than blocking for more input. If the channel is configured to use a multi-byte |
encoding, then there may actually be some bytes remaining in the internal buffers that do not form a complete character. These bytes will |
not be returned until a complete character is available or end-of-file is reached. The -nonewline switch is ignored if the command returns
before reaching the end of the file.
Read translates end-of-line sequences in the input into newline characters according to the -translation option for the channel. See the
fconfigure manual entry for a discussion on ways in which fconfigure will alter input.
SEE ALSO
file(n), eof(n), fblocked(n), fconfigure(n)
KEYWORDS
blocking, channel, end of line, end of file, nonblocking, read, translation, encoding
Tcl 8.1 read(n)