Because shell word splitting occurs before variable expansion, when you run the script like this:
the shell tries to execute the following command:
So the shell is looking for a command named add.ksh -customer 4875 ..., not for command/script named add.ksh.
The argument passed to eval is evaluated twice, in your case first the variable is expanded, than the ordinary processing is attempted: redirection, shell word splitting, variable expansion (if any variable is left) etc, so the shell sees the correct command and executes it.
As I said, it would be safer to use the second approach.
I have a server that receives backup files from several servers. Each server has its own directory to scp their files into, some of the files are received as .tar files and need to be compressed before being dumped. When the scp of the tar file is complete a file named 'flag' is also sent to... (2 Replies)
Hello
I am executing the following script
nawk 'NR == 1 || substr($0,63,5) ~ /H... / && \
_++ == 2 { fn && close(fn); fn = "part_" ++c; _ = 1 }
{ print > fn }' sample.dat
When i execute as it is it is executing fine. but when i execute the whole script as a single line like below
... (2 Replies)
I am executing the below in telnet
#!/usr/bin/ksh
File1=simple.txt # The file to check
LogFile=simple.log # The log file
DelayMax=30 # Timeout delay
Tolerance=2
# BEGIN ##############################
while true
do
StampNow=$(date +%s)/60 # stamp in minutes
... (3 Replies)
Hi ,
I m getting an error after executing the script.
My script.
Script is used to find out the date on 8 different machines(mentioned in SERVERNAMES file).
I have added public key to avoid ssh password and ssh without password working fine.
#!/bin/sh
fn_VMFind()
{
Date=`ssh -t... (5 Replies)
Hi
Please assist. Im getting an error while execuing the script name d "cdsnd.basel.cd_new
" as siiadm user. Thanks.
siiadm> ls -l
total 64
-rwxr-xr-x 1 siiadm sboadm 1004 Sep 17 2008 cdsnd.basel.cd
-rwxr-xr-x 1 siiadm sapsys 998 Nov 16 09:14 cdsnd.basel.cd_new... (1 Reply)
I am facing this weird issue where the script is working fine from the command line but when I am executing it from cron though it is working fine but the "if" loop is processing else part though I know that the if part of the logic is true and ideally the loop should execute the if portion.
... (3 Replies)
I have the following script test.sh owned by dwdev account and group dwdev, the permissions on the script are as follows.
-rw-r-x--- 1 dwdev dwdev 279 Sep 17 13:19 test.sh
Groups:
cat /etc/group | grep dwdev
dwdev:x:704:dwdev
dwgroup:x:725:dwdev
writers:x:726:dwdev
User:
cat /etc/passwd |... (3 Replies)
Hi,
I wrote this script to test if the output for DIR1 and DIR2 comes out as I want :
#!/bin/bash
DAY=$(date +%d)
MONTH=$(date +%b)
YEAR=$(date +%Y)
DIR1=$($MONTH$YEAR"_Blast_BC01")
DIR2=$($MONTH$YEAR"_Blast_BC15")
echo $DIR1
echo $DIR2
This is the output I want for echo $DIR1 ... (12 Replies)
Discussion started by: anaigini45
12 Replies
LEARN ABOUT X11R4
exec
exec(1) User Commands exec(1)NAME
exec, eval, source - shell built-in functions to execute other commands
SYNOPSIS
sh
exec [argument...]
eval [argument...]
csh
exec command
eval argument...
source [-h] name
ksh
*exec [arg...]
*eval [arg...]
DESCRIPTION
sh
The exec command specified by the arguments is executed in place of this shell without creating a new process. Input/output arguments may
appear and, if no other arguments are given, cause the shell input/output to be modified.
The arguments to the eval built-in are read as input to the shell and the resulting command(s) executed.
csh
exec executes command in place of the current shell, which terminates.
eval reads its arguments as input to the shell and executes the resulting command(s). This is usually used to execute commands generated as
the result of command or variable substitution.
source reads commands from name. source commands may be nested, but if they are nested too deeply the shell may run out of file descrip-
tors. An error in a sourced file at any level terminates all nested source commands.
-h Place commands from the file name on the history list without executing them.
ksh
With the exec built-in, if arg is given, the command specified by the arguments is executed in place of this shell without creating a new
process. Input/output arguments may appear and affect the current process. If no arguments are given the effect of this command is to mod-
ify file descriptors as prescribed by the input/output redirection list. In this case, any file descriptor numbers greater than 2 that are
opened with this mechanism are closed when invoking another program.
The arguments to eval are read as input to the shell and the resulting command(s) executed.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
EXIT STATUS
For ksh:
If command is not found, the exit status is 127. If command is found, but is not an executable utility, the exit status is 126. If a redi-
rection error occurs, the shell exits with a value in the range 1-125. Otherwise, exec returns a zero exit status.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), ksh(1), sh(1), attributes(5)SunOS 5.10 17 Jul 2002 exec(1)