Sponsored Content
Full Discussion: while loops
Top Forums Shell Programming and Scripting while loops Post 302070100 by Perderabo on Friday 31st of March 2006 11:59:58 AM
Old 03-31-2006
Code:
#! /usr/bin/ksh

exec < file
while read line ; do
        [[ "$line" = *"Media ID="* ]] && echo ${line#*=}
        [[ "$line" = *"Type="* ]] && echo ${line#*=}
done
exit 0

 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

loops?

hello....very new user to unix...and i have a question..i am not sure if there is such a thing For example...the user is asked if he likes Bananas....if he says yes.... echo You like Bananas $name at the end of the script it echos all that the user has entered so they can read it.... but... (1 Reply)
Discussion started by: jonas27
1 Replies

2. Shell Programming and Scripting

Loops within loops

I am running on HPUX using ksh. I have a script that uses a loop within a loop, for some reason the script seems to hang on a particuliar record. The record is fine and hits the condition in Blue. If I kill the 1st loop process the script continues on with no problem. Begin code> <Some... (8 Replies)
Discussion started by: bthomas
8 Replies

3. UNIX for Dummies Questions & Answers

While Loops

I'm trying to create a loop that will prompt the user for 15 values, not forcing them to enter all 15. If the user enters through one or more of the prompts the null value needs to be converted to 0, otherwise set the parameter = to the value entered: ex. Please enter file no #1: 17920 ... (4 Replies)
Discussion started by: vdc
4 Replies

4. UNIX for Dummies Questions & Answers

two loops

Hi, how can I use "for" to have two loops : this is my script : for i in (A B C) do for j in (a b c) do echo $i$j done done #End I want to print out Aa Ab Ac .... But I have error message : syntax error at line 1 : `(' unexpected Many thanks before. How should I use "for" ?? (2 Replies)
Discussion started by: big123456
2 Replies

5. UNIX for Dummies Questions & Answers

Help with While Loops

I am traversing down a list, and I am not quite sure how to tell the loop to break when it's done going through the file. #!/bin/sh while : do read list <&3 echo $list done is the code. The file "list" is simply 5 4 3 2 1 any advice on how to break the loop after the file is... (1 Reply)
Discussion started by: MaestroRage
1 Replies

6. Shell Programming and Scripting

Help with the 2 for loops

#!/bin/bash IFS=$'\n' A= a c b t g j i e d B= t y u i o p counter=0 found="" for i in $(cat $A) do for j in $(cat $B) do if then found="yes" fi done if then (1 Reply)
Discussion started by: vadharah
1 Replies

7. Shell Programming and Scripting

Loops

Hi All, I want to execute a script the number of times a user enters. Please can you advise on hor can I do the same. Many Thanks, Shazin (4 Replies)
Discussion started by: Shazin
4 Replies

8. UNIX for Dummies Questions & Answers

loops with tr

Hello, I'm not sure if this is more appropriate for the 'unix for dummies' or the 'unix for experts' forum because I'm new to this forum and this is the second topic I've discussed, but if you could let me know which one was more appropriate for something like this, please do! So in tr (an... (2 Replies)
Discussion started by: juliette salexa
2 Replies

9. UNIX for Advanced & Expert Users

Help with loops?

I'm trying to understand better the while and until loops, can someone help me with this example? #!/bin/bash # Listing the planets. for planet in Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto do echo $planet # Each planet on a separate line. done echo; echo for... (3 Replies)
Discussion started by: jose2802
3 Replies

10. UNIX for Dummies Questions & Answers

Need help with for loops

Why wont my for statements work? Im trying to get this script to swich to a user an if you put in a start/stop/or restart paramater to do just that for each user. I commented out the actual start/stop actions to test it just by using echos and not do anything hasty in the environment but it... (0 Replies)
Discussion started by: LilyClaro
0 Replies
read(1)                                                            User Commands                                                           read(1)

NAME
read - read a line from standard input SYNOPSIS
/usr/bin/read [-r] var... sh read name... csh set variable = $< ksh read [ -prsu [n]] [ name ? prompt] [name...] DESCRIPTION
/usr/bin/read The read utility will read a single line from standard input. By default, unless the -r option is specified, backslash () acts as an escape character. If standard input is a terminal device and the invoking shell is interactive, read will prompt for a continuation line when: o The shell reads an input line ending with a backslash, unless the -r option is specified. o A here-document is not terminated after a NEWLINE character is entered. The line will be split into fields as in the shell. The first field will be assigned to the first variable var, the second field to the second variable var, and so forth. If there are fewer var operands specified than there are fields, the leftover fields and their interven- ing separators will be assigned to the last var. If there are fewer fields than vars, the remaining vars will be set to empty strings. The setting of variables specified by the var operands will affect the current shell execution environment. If it is called in a subshell or separate utility execution environment, such as one of the following: (read foo) nohup read ... find . -exec read ... ; it will not affect the shell variables in the caller's environment. The standard input must be a text file. sh One line is read from the standard input and, using the internal field separator, IFS (normally space or tab), to delimit word boundaries, the first word is assigned to the first name, the second word to the second name, and so on, with leftover words assigned to the last name. Lines can be continued using ewline. Characters other than NEWLINE can be quoted by preceding them with a backslash. These backslashes are removed before words are assigned to names, and no interpretation is done on the character that follows the backslash. The return code is 0, unless an end-of-file is encountered. csh The notation: set variable = $< loads one line of standard input as the value for variable. (See csh(1)). ksh The shell input mechanism. One line is read and is broken up into fields using the characters in IFS as separators. The escape character, (), is used to remove any special meaning for the next character and for line continuation. In raw mode, -r, the character is not treated specially. The first field is assigned to the first name, the second field to the second name, and so on, with leftover fields assigned to the last name. The -p option causes the input line to be taken from the input pipe of a process spawned by the shell using |&. If the -s flag is present, the input will be saved as a command in the history file. The flag -u can be used to specify a one digit file descriptor unit n to read from. The file descriptor can be opened with the exec special command. The default value of n is 0. If name is omitted, REPLY is used as the default name. The exit status is 0 unless the input file is not open for reading or an end-of-file is encoun- tered. An end-of-file with the -p option causes cleanup for this process so that another can be spawned. If the first argument contains a ?, the remainder of this word is used as a prompt on standard error when the shell is interactive. The exit status is 0 unless an end-of- file is encountered. OPTIONS
The following option is supported: -r Does not treat a backslash character in any special way. Considers each backslash to be part of the input line. OPERANDS
The following operand is supported: var The name of an existing or non-existing shell variable. EXAMPLES
Example 1: An example of the read command The following example for /usr/bin/read prints a file with the first field of each line moved to the end of the line: example% while read -r xx yy do printf "%s %s " "$yy" "$xx" done < input_file ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables that affect the execution of read: LANG, LC_ALL, LC_CTYPE, LC_MES- SAGES, and NLSPATH. IFS Determines the internal field separators used to delimit fields. PS2 Provides the prompt string that an interactive shell will write to standard error when a line ending with a backslash is read and the -r option was not specified, or if a here-document is not terminated after a newline character is entered. EXIT STATUS
The following exit values are returned: 0 Successful completion. >0 End-of-file was detected or an error occurred. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), ksh(1), line(1), set(1), sh(1), attributes(5), environ(5), standards(5) SunOS 5.10 28 Mar 1995 read(1)
All times are GMT -4. The time now is 05:59 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy