Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: `do' unexpected -> Error message
Top Forums Shell Programming and Scripting `do' unexpected -> Error message Post 302943072 by bakunin on Tuesday 5th of May 2015 07:42:11 AM
Old 05-05-2015
Quote:
Originally Posted by gsiva
Am I missing something ???
As it is: yes. You have been given ample help already on how to construct the for-loop syntactically correct. IMHO this is one side of the story. My advice is to avoid for-loops for things like yours altogether and use while-loops instead:

instead of

Code:
for VAR in $(command -producing | some | list) ; do
     something $VAR
done

do

Code:
command -producing | some | list |\
while read VAR ; do
     something $VAR
done

There are two reasons for this:

first, "for" parses words, not lines. If one of the list of items the command produces contains a whitespace it will break. The "while read ..." will parse on lines and as long as on each line is only one value you are fine even if the values themselves contain whitespace.

second, there is a maximum line length and a maximum number of arguments a command can take in place. These values have been increased with the advent of 64-bit OSes but they are still there and whatever you feed into "for" is an argument to it. For instance:

Code:
 for i in 1 2 3 4 5 ; do .... done

gives 5 arguments, "1", "2", etc., to "for". Because your process substitution ("$(...)" or backticks) can produce any number of arguments without you having control over the process. It may never really hit you but why the take the risk? The while-loop will have no restriction in the number of elements it can process because it handles one item at a time.

I hope this helps.

bakunin
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

"syntax error at line 21 :'done' unexpected." error message"

I am trying to run the script bellow but its given me "syntax error at line 20 :'done' unexpected." error message" can someone check to see if the script is ok? and correct me pls. Today is my first day with scripting. Gurus should pls help out #!/bin/ksh # Purpose: Check to see if file... (3 Replies)
Discussion started by: ibroxy
3 Replies

2. UNIX for Dummies Questions & Answers

awk Shell Script error : "Syntax Error : `Split' unexpected

hi there i write one awk script file in shell programing the code is related to dd/mm/yy to month, day year format but i get an error please can anybody help me out in this problem ?????? i give my code here including error awk ` # date-month -- convert mm/dd/yy to month day,... (2 Replies)
Discussion started by: Herry
2 Replies

3. UNIX for Dummies Questions & Answers

unexpected error

./sample.5: syntax error: `(' unexpected I get this error and Im trying to solve it but the line that it refering to is a notation so I don't understand why it is affecting the program. (2 Replies)
Discussion started by: helpme2008
2 Replies

4. Shell Programming and Scripting

sed error : Syntax error: redirection unexpected

My script is throwing the error 'Syntax error: redirection unexpected' My line of code.. cat nsstatustest.html | sed s/<tr><td align="left">/<tr><td align="left" bgcolor="#000000"><font color="white">/ > ztmp.Ps23zp2s.2-Fpps3-wmmm0dss3 HTML tags are getting in the way but they're needed to... (3 Replies)
Discussion started by: phpfreak
3 Replies

5. Solaris

Unexpected error

When I typed #svcs -x sma I received this following error, svcs: svcs.c:335: Unexpected libscf error: invalid argument. Exiting. I have googled around but could not find a solution. IS this a bug? I am using Solaris 5.10 Generic_137137-09 sun4v sparc... (2 Replies)
Discussion started by: sundar63
2 Replies

6. Shell Programming and Scripting

Getting unexpected error

Hi All, I am writing one script to automate one of the process and for that I am using below command at one line : uncompress `cat tmp` content in tmp file are : /home/vas/aqbatch/newbatch/archive/output/RIM_GUIDEPRICE_AQ_02108.DAT.Z... (5 Replies)
Discussion started by: NirajThakar
5 Replies

7. Shell Programming and Scripting

IF section problem. syntax error: unexpected end of file error

Hello, I have another problem with my script. Please accept my apologies, but I am really nooby in sh scripts. I am writing it for first time. My script: returned=`tail -50 SapLogs.log | grep -i "Error"` echo $returned if ; then echo "There is no errors in the logs" fi And after... (10 Replies)
Discussion started by: jedzio
10 Replies

8. Shell Programming and Scripting

Syntax error: 'fi' unexpected

unzip file.zip if ] ; then echo "Success" else echo "Some failure." fi ; I tried many time to detect the unzip error, but it keep show the syntax error wherever how I change the syntac. Hope someone can help me fix the issue, thanks. Please use code tags next time for your code and... (5 Replies)
Discussion started by: duncanyy
5 Replies

9. Shell Programming and Scripting

Syntax error `(' unexpected

I have written this in my script but while running i am getting syntax error `(' unexpected. unload to "$BACKUP_DIR/n_fac_fid-$clliname" select * from n_fac_fid where fac_accesskey in (select fac_accesskey From n_fac_ap_fid where ap_clli="$clliname"); Any help appreciated. (3 Replies)
Discussion started by: suryanmi
3 Replies

10. UNIX for Beginners Questions & Answers

Getting this error syntax error near unexpected token `)'

Hi Everyone, my script was running Ok, but suddenly it started giving this error. ./update_env_bi.sh: line 54: syntax error near unexpected token `)' ./update_env_bi.sh: line 54: `sed -i "s/PORT=*1/PORT=$2/" repository.xml' The line 54 has this code. sed -i "s/PORT=*1/PORT=$2/"... (2 Replies)
Discussion started by: shajay12
2 Replies

LEARN ABOUT LINUX

anacrontab

ANACRONTAB(5)						       Anacron Users' Manual						     ANACRONTAB(5)

NAME

       /etc/anacrontab - configuration file for anacron

DESCRIPTION

       The file /etc/anacrontab describes the jobs controlled by anacron(8).  Its lines can be of three kinds:	job-description lines, environment
       assignments, or empty lines.

       Job-description lines are of one of these two forms:

	  period  delay  job-identifier  command

	  @period_name delay job-identify command

       The period is specified in days, the delay in minutes.  The job-identifier can contain any non-blank character, except slashes.	It is used
       to  identify  the  job in Anacron messages, and as the name for the job's timestamp file.  The command can be any shell command. The fields
       can be separated by blank spaces or tabs.  The period_name can only be set to monthly at the present time. This will ensure jobs  are  only
       run once a month, no matter the number of days in this month, or the previous month.

       Environment assignment lines are of the form:

	  VAR = VALUE

       Spaces  around  VAR  are removed.  No spaces around VALUE are allowed (unless you want them to be part of the value).  The assignment takes
       effect from the next line to the end of the file, or to the next assignment of the same variable.

       Empty lines are either blank lines, line containing white-space only, or lines with white-space followed by a '#' followed by an  arbitrary
       comment.

       You can continue a line onto the next line by ending it with a ''.

SEE ALSO

       anacron(8)

       The Anacron README file.

AUTHOR

       Itai Tzur <itzur@actcom.co.il>

       Currently maintained by Pascal Hakim <pasc@(debian.org|redellipse.net)>.

Pascal Hakim							    2004-07-11							     ANACRONTAB(5)
All times are GMT -4. The time now is 05:51 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy