Sponsored Content
Top Forums UNIX for Advanced & Expert Users [Discussion] POSIX, the Love of Backticks and All That Jazz Post 302990402 by MadeInGermany on Thursday 26th of January 2017 03:56:31 AM
Old 01-26-2017
Bug

Then let me continue with lession#2.
Within $( ) there is a parser problem with the old style case statements.
Code:
#!/bin/bash
res=$(
  case $1 in
  1) echo 1;;
  esac
)
# syntax error in bash3 and ksh88
# workaround:
# (1) echo 1;;
echo "$res"

But bash4 and ksh93 have got a fix.
This User Gave Thanks to MadeInGermany For This Post:
 

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Perl - backticks v system in if statements

Can someone explain the difference between backticks and system when evaluated in these if statements: sub getDate { print "start date\n"; if ( system("/bin/date") ) { print "can't get date\n"; exit(2); } print "finish date\n"; } Returns the following: start date Thu... (5 Replies)
Discussion started by: gjkeenan
5 Replies

2. Shell Programming and Scripting

Backticks within backticks?

Hi, I'm trying to do something like this: range= `expr `date '+%m'` - 1` and it does not work. How can I tell it to evaluate an expression within another expression evaluation? I was at first worried that `date '+%m'` would return a string but apparently expr does the math okay normally, so the... (3 Replies)
Discussion started by: jeriryan87
3 Replies

3. UNIX for Dummies Questions & Answers

sed: removing backticks from certain lines

Hi, I would like to change some lines in my mysql-dump, because there a syntax problems with some version of mysql. I 'd like to change USE ´someDatabase´; to USE someDatabase; (without backticks) using the sed command in the shell Thanks & best regards Bernd (5 Replies)
Discussion started by: bjb
5 Replies

4. Shell Programming and Scripting

Am I abusing backticks?

I'm always concerned I might be abusing backticks within my scripts. A current script I'm writing has this for example: stripscriptname=`echo $scriptname | sed 's/\(.*\)\..*/\1/'` stripsearch=`echo $searchpattern | tr -d ' ,/'` Both of these variables are set inside the script (in fact,... (2 Replies)
Discussion started by: mglenney
2 Replies

5. Shell Programming and Scripting

Difference between using xargs and backticks

Hey all. Just a fast question, what is the technical difference between using back ticks and using xargs to perform a command? Here's an example Find /mydir -name *.conf |xargs rm Vs Rm 'find /mydir -name *.conf' Is there a performance hit? I know they do the same thing but which is... (1 Reply)
Discussion started by: msarro
1 Replies

6. Red Hat

perl backticks: can't redirect output.

Hi everyone. This is a bit of a perl/linux mixed question. I am trying to redirect STDOUT of chsh by using the following line of perl code. system ("chsh -s /sbin/nologin $testing 1>/dev/null"); This should redirect STDOUT to /dev/null but it won't do that for some odd reason. Any ideas or... (6 Replies)
Discussion started by: austinharris43
6 Replies

7. Shell Programming and Scripting

Help with remove backticks in a text file

Input file: 'data_1' 'data_10' 'data1311' '235data_13' Desired output: data_1 data_10 data1311 235data_13 Can I know how to remove back tick"'" in a file? Many thanks for advice. (3 Replies)
Discussion started by: perl_beginner
3 Replies

8. Shell Programming and Scripting

SSH and Backticks [solved]

I have been testing a new script and cannot figure out why my `cat spath` will not execute on the remote machine? sudo ssh -p 22344 -o "PasswordAuthentication no" -o "HostbasedAuthentication yes" -l testuser 192.168.1.6 "find `cat spath` -depth" cat: spath: No such file or directory but... (0 Replies)
Discussion started by: metallica1973
0 Replies

9. Shell Programming and Scripting

Nesting backticks

I'm trying to make a dialog window that prints the output of grep that takes the output of find. Unfortunately my nested backticks don't work. Here is the dialog window: dialog --stdout --title "test" --backtitle "test" --msgbox "Test:\n `grep -l "${tablica}" `find $string``" 16 60I think I... (2 Replies)
Discussion started by: Starting_Leaf
2 Replies
PG_FIELD_PRTLEN(3)														PG_FIELD_PRTLEN(3)

pg_field_prtlen - Returns the printed length

SYNOPSIS
int pg_field_prtlen (resource $result, int $row_number, mixed $field_name_or_number) DESCRIPTION
int pg_field_prtlen (resource $result, mixed $field_name_or_number) pg_field_prtlen(3) returns the actual printed length (number of characters) of a specific value in a PostgreSQL $result. Row numbering starts at 0. This function will return FALSE on an error. $field_name_or_number can be passed either as an integer or as a string. If it is passed as an integer, PHP recognises it as the field num- ber, otherwise as field name. See the example given at the pg_field_name(3) page. Note This function used to be called pg_fieldprtlen(3). PARAMETERS
o $result - PostgreSQL query result resource, returned by pg_query(3), pg_query_params(3) or pg_execute(3) (among others). o $row - Row number in result. Rows are numbered from 0 upwards. If omitted, current row is fetched. RETURN VALUES
The field printed length, or FALSE on error. EXAMPLES
Example #1 Getting information about fields <?php $dbconn = pg_connect("dbname=publisher") or die("Could not connect"); $res = pg_query($dbconn, "select * from authors where author = 'Orwell'"); $i = pg_num_fields($res); for ($j = 0; $j < $i; $j++) { echo "column $j "; $fieldname = pg_field_name($res, $j); echo "fieldname: $fieldname "; echo "printed length: " . pg_field_prtlen($res, $fieldname) . " characters "; echo "storage length: " . pg_field_size($res, $j) . " bytes "; echo "field type: " . pg_field_type($res, $j) . " "; } ?> The above example will output: column 0 fieldname: author printed length: 6 characters storage length: -1 bytes field type: varchar column 1 fieldname: year printed length: 4 characters storage length: 2 bytes field type: int2 column 2 fieldname: title printed length: 24 characters storage length: -1 bytes field type: varchar SEE ALSO
pg_field_size(3). PHP Documentation Group PG_FIELD_PRTLEN(3)
All times are GMT -4. The time now is 05:18 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy