read [ -ACprsv ] [ -d delim] [ -n n] [ [ -N n] [ [ -t timeout] [ -u unit] [ vname?prompt ] [ vname ... ]
The shell input mechanism. One line is read and is broken up into fields using the characters in IFS as separators. The escape charac-
ter, \, is used to remove any special meaning for the next character and for line continuation. The -d option causes the read to con-
tinue to the first character of delim rather than new-line. The -n option causes at most n bytes to read rather a full line but will
return when reading from a slow device as soon as any characters have been read. The -N option causes exactly n to be read unless an
end-of-file has been encountered or the read times out because of the -t option. In raw mode, -r, the \ character is not treated spe-
cially. The first field is assigned to the first vname, the second field to the second vname, etc., with leftover fields assigned to
the last vname. When vname has the binary attribute and -n or -N is specified, the bytes that are read are stored directly into the
variable. If the -v is specified, then the value of the first vname will be used as a default value when reading from a terminal
device. The -A option causes the variable vname to be unset and each field that is read to be stored in successive elements of the
indexed array vname. The -C option causes the variable vname to be read as a compound variable. Blanks will be ignored when finding
the beginning open parenthesis. The -p option causes the input line to be taken from the input pipe of a process spawned by the shell
using â&. If the -s option is present, the input will be saved as a command in the history file. The option -u can be used to specify
a one digit file descriptor unit unit to read from. The file descriptor can be opened with the exec special built-in command. The
default value of unit n is 0. The option -t is used to specify a timeout in seconds when reading from a terminal or pipe. If vname is
omitted, then REPLY is used as the default vname. 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 or read has timed out.
i don't get what's wrong here. i'm writing a shell script that takes 1 argument (a number) from the command-line, but it's throwing an error:
Syntax error: Bad for loop variable
doesn't make much sense
for (( i = 1; i = ${1}; i++ )) # error points to this line everytime
do
echo... (9 Replies)
Hi,
I have the following script (compile_mercury) and I get this error: I have no idea why...and I have written this script completely in linux (bash) and not in windows.
****************
./compile_mercury: line 136: syntax error near unexpected token `done'
./compile_mercury: line 136:... (1 Reply)
Hi guys,
I'm trying to loop through a number of files that is set by whatever is in a field.
eg.
The idea is to split FILELIST down into fields, it could contain 1 - 999 fields and it's bar delimited.
I thought simple, count the number of fields in the field and then loop... (1 Reply)
hi,
I have to use for loop in my script. The below code is providing an output,
1,2,3,4,5..n. But i need to display the values one by one eg: it has to display the first value then exit from the loop and display the second value then exit till n(last value).
for i in 1,2,3,4,5..n
do ... (2 Replies)
I am trying to run a menu option though IF loops. I keep getting errors not allowed the menu to be processed correctly. Currently it will accept the first 2 statements but then crash on the 3rd. The 2nd and 3rd have the same syntax, so I do not understand why it breaks.
#!/bin/bash
while... (4 Replies)
can some one please tell me what is the problem with my syntax:confused:
I have 100 files in one folder
1. want to read each of the line by line
2. calculate their number of the words between the first word and the last word of each line
3. create file for each file with number of words... (8 Replies)
I am using simple for loop, but getting syntax error when I run the code
code
#!/bin/ksh
pls enter number
read n
for(i=1; i<=n; i++)
do
echo $i
done
syntax error
+ pls enter number
+ read n (5 Replies)
I like to “optimize” / make more like a real program my bash script by replacing repetitious code which utilizes positional parameters.
I am having two issues I cannot solve and would appreciate some assistance with resolving them.
a) how to modify the whiptail checklist... (3 Replies)
Discussion started by: annacreek
3 Replies
LEARN ABOUT NETBSD
break
break(1) User Commands break(1)NAME
break, continue - shell built-in functions to escape from or advance within a controlling while, for, foreach, or until loop
SYNOPSIS
sh
break [n]
continue [n]
csh
break
continue
ksh
*break [n]
*continue [n]
DESCRIPTION
sh
The break utility exits from the enclosing for or while loop, if any. If n is specified, break n levels.
The continue utility resumes the next iteration of the enclosing for or while loop. If n is specified, resume at the n-th enclosing loop.
csh
The break utility resumes execution after the end of the nearest enclosing foreach or while loop. The remaining commands on the current
line are executed. This allows multilevel breaks to be written as a list of break commands, all on one line.
The continue utility continues execution of the next iteration of the nearest enclosing while or foreach loop.
ksh
The break utility exits from the enclosed for, while, until, or select loop, if any. If n is specified, then break n levels. If n is
greater than the number of enclosing loops, the outermost enclosing loop shall be exited.
The continue utility resumes the next iteration of the enclosed for, while, until, or select loop. If n is specified then resume at the n-
th enclosed loop. If n is greater than the number of enclosing loops, the outermost enclosing loop shall be used.
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 that follow 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 also that word splitting and file name genera-
tion are not performed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), exit(1), ksh(1), sh( 1), attributes(5)SunOS 5.10 17 Jul 2002 break(1)