08-20-2008
how to see if the file is empty or not?
hi
how can I determine, if a file is empty or not?I am using read line clause.
The script should be like:
while read line
do
if(file is empty) then;
......
done < $blacklist
10 More Discussions You Might Find Interesting
1. UNIX for Advanced & Expert Users
Hi,
I need your help.
How can I create an empty filename with a specific size, in hp-ux?
Regards,
Mizi (2 Replies)
Discussion started by: Mizi
2 Replies
2. Shell Programming and Scripting
What is the command to empty an already existing file.
please provide me.i used Touch cmd to empty the file.but it changing the time only. (4 Replies)
Discussion started by: laknar
4 Replies
3. Shell Programming and Scripting
How do I check to make sure a file is not zero bytes?
Something like:
if
then
????? (7 Replies)
Discussion started by: lesstjm
7 Replies
4. UNIX for Dummies Questions & Answers
hi all:
my solaris FIND does not support
find myFolder -type d -empty
how can i find the empty folders?
thanks! (7 Replies)
Discussion started by: lasse
7 Replies
5. UNIX for Dummies Questions & Answers
AIX 5.3 / KSH
I have a Java application which creates a log file a.log. I have a KSH script which does the following action
cp a.log /directory2/b.log
> a.log
After this the file size goes to 0 as per "ls -l"
Then next time when the application writes into this file, the file size... (4 Replies)
Discussion started by: firdousamir
4 Replies
6. UNIX for Dummies Questions & Answers
Hi All,
I am checking for a empty input file to do some further action , but I am getting exit status 0 in both the cases , for empty and non empty file both.
The value of $? is coming 0 in if part also and else part too.
#!/bin/ksh
if ]; then
echo "data"
# exit 0
echo "$?"
else... (4 Replies)
Discussion started by: mavesum
4 Replies
7. Shell Programming and Scripting
how can i use while loop ?
while file is empty do....
if not empty do .....
in bash (1 Reply)
Discussion started by: Trump
1 Replies
8. Shell Programming and Scripting
Hi All,
I have a piece of perl code in which I DON'T want to delete a file rather empty out the contents, here is the code -
if ( unlink("$opt_b") == 1 ) {
print_log( "$opt_b deleted", 1 );
}else {
print_log( "Could not delete $opt_b:$!", 1 );
... (5 Replies)
Discussion started by: jacki
5 Replies
9. Shell Programming and Scripting
Hi there,
I'm just starting out with shell scripting and I'm trying to make a test where the script will basically run yum check-update to find out if the server has any available and if it does it e-mails me but if not it will just stop there.
I have it working if there are actually... (7 Replies)
Discussion started by: Imnewtothis
7 Replies
10. Shell Programming and Scripting
The below awk improved bu @MadeInGermany, works great as long as the input file has data in it in the below format:
input
chrX 25031028 25031925 chrX:25031028-25031925 ARX 631 18
chrX 25031028 25031925 chrX:25031028-25031925 ARX 632 14... (3 Replies)
Discussion started by: cmccabe
3 Replies
LEARN ABOUT XFREE86
dnsblog
DNSBLOG(8postfix) DNSBLOG(8postfix)
NAME
dnsblog - Postfix DNS white/blacklist logger
SYNOPSIS
dnsblog [generic Postfix daemon options]
DESCRIPTION
The dnsblog(8) server implements an ad-hoc DNS white/blacklist lookup service. This may eventually be replaced by an UDP client that is
built directly into the postscreen(8) server.
PROTOCOL
With each connection, the dnsblog(8) server receives a DNS white/blacklist domain name, an IP address, and an ID. If the IP address is
listed under the DNS white/blacklist, the dnsblog(8) server logs the match and replies with the query arguments plus an address list with
the resulting IP addresses, separated by whitespace, and the reply TTL. Otherwise it replies with the query arguments plus an empty
address list and the reply TTL; the reply TTL is -1 if there is no reply, or a negative reply that contains no SOA record. Finally, the
dnsblog(8) server closes the connection.
DIAGNOSTICS
Problems and transactions are logged to syslogd(8).
CONFIGURATION PARAMETERS
Changes to main.cf are picked up automatically, as dnsblog(8) processes run for only a limited amount of time. Use the command "postfix
reload" to speed up a change.
The text below provides only a parameter summary. See postconf(5) for more details including examples.
config_directory (see 'postconf -d' output)
The default location of the Postfix main.cf and master.cf configuration files.
daemon_timeout(18000s)
How much time a Postfix daemon process may take to handle a request before it is terminated by a built-in watchdog timer.
postscreen_dnsbl_sites (empty)
Optional list of DNS white/blacklist domains, filters and weight factors.
ipc_timeout(3600s)
The time limit for sending or receiving information over an internal communication channel.
process_id (read-only)
The process ID of a Postfix command or daemon process.
process_name (read-only)
The process name of a Postfix command or daemon process.
queue_directory (see 'postconf -d' output)
The location of the Postfix top-level queue directory.
syslog_facility (mail)
The syslog facility of Postfix logging.
syslog_name (see 'postconf -d' output)
A prefix that is prepended to the process name in syslog records, so that, for example, "smtpd" becomes "prefix/smtpd".
Available in Postfix 3.3 and later:
service_name (read-only)
The master.cf service name of a Postfix daemon process.
SEE ALSO
smtpd(8), Postfix SMTP server
postconf(5), configuration parameters
syslogd(5), system logging
LICENSE
The Secure Mailer license must be distributed with this software.
HISTORY
This service was introduced with Postfix version 2.8.
AUTHOR(S)
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
Wietse Venema
Google, Inc.
111 8th Avenue
New York, NY 10011, USA
DNSBLOG(8postfix)