hi all. i have a little problem. im basically reading input from the user from the keyboard into the variable "phonenumber". I want to do a little error check to check if the user doesnt enter anything in for the value phonenumber.
i had this:
read phonenumber
if
then
.....
else
........ (2 Replies)
Hi everyone - I am sure this is a really simple problem but I'm a total noob at Linux scripting:
I wanted to create a script that allows me to compare the current week number to the contents of a text file in my home directory:
VAR1='date +%V'
VAR2='cat /home/fred/file.txt'
... (6 Replies)
Hi
New to shell script and awk and need assistance on this problem. I need to use a variable to substitute a string in an external file and write the changed info to another file.
At first I did not know if you could use a variable as the sub value but the following showed me that I can.
... (3 Replies)
Hello;
Trying to figure out how to keep just the contents between the two search lines:
awk '/regexp_1/ ,/regexp_2/'
I do not want lines containing regexp_1 and regexp_2 in the output.
Thank you for any ideas
Video tutorial on how to use code tags in The UNIX and Linux Forums. (5 Replies)
Hello;
I need to print two previous lines after searching for a reg exp:
awk '/haywood/'
should produce the following
===================
p9J46THe020804 89922 Tue Oct 18 21:06 MAILER-DAEMON
(host map: lookup (haywood.com): deferred)
... (1 Reply)
Hello;
we have :
awk '/reg_exp/,0/
prints every line after the first occurrence of "reg_exp"
But if I want to print rest of the lines AFTER the last occurrence of "reg_exp",
how would I do it ??
Tried :
awk ' ! (/reg_exp/,0)'
But it errored...
Thank you for any... (5 Replies)
Discussion started by: delphys
5 Replies
LEARN ABOUT REDHAT
sum
sum(n) sum sum(n)
NAME
sum - calculate a sum(1) compatible checksum
SYNOPSIS
package require Tcl 8.2
package require sum ?1.0?
::crc::sum ?-format format? message
::crc::sum ?-format format? -filename file
DESCRIPTION
This package provides a Tcl-only implementation of the sum(1) command which calculates a 16 bit checksum value from the input data. The
BSD sum algorithm is used by default but the SysV algorithm is also available.
COMMANDS
::crc::sum ?-format format? message
::crc::sum ?-format format? -filename file
The command takes string data or a file name and returns a checksum value calculated using the sum(1) algorithm. The result is for-
matted using the format(n) specifier provided or as an unsigned integer (%u) by default.
OPTIONS -filename name
Return a checksum for the file contents instead of for parameter data.
-format string
Return the checksum using an alternative format template.
EXAMPLES
% crc::sum "Hello, World!"
37287
% crc::sum -format 0x%X "Hello, World!"
0x91A7
% crc::sum -file sum.tcl
13392
SEE ALSO sum(1), cksum(n), crc32(n)
AUTHORS
Pat Thoyts
KEYWORDS
sum, cksum, checksum, crc, crc32, cyclic redundancy check, data integrity, security
crc 1.0 sum(n)