hi,I am new to shell script,I have String,like this:
Number of rows exported: 5321
the numbe at end could changing,how can I extract this number and assign it to a variable,then use it later in script.
thanks. (19 Replies)
Is there any way to print all the string till we get a space and a number and store it a variable
for eg we have string java.io.IOException: An existing connection was forcibly closed by the remote host 12
All I want is to store "java.io.IOException: An existing connection was forcibly closed... (13 Replies)
I need to add space to certain directory. I believe I need to add space to the filesystem this directory belongs to. How can I find out what filesystem this directory belongs to? (3 Replies)
Hi,
I need to generate the text name dynamically in for loop,
ex,
VAR_COPY_FILE1= file path 1
VAR_COPY_FILE2= file path 2
VAR_COPY_FILE3= file path 3
for i in 1 2 3
do
if
then
"do some process here"
fi
done (3 Replies)
I am parsing a file and I get differnt results everytime.
Sometimes I get 12s sometimes I get 54m and sometime 3h..
v1=12s or v1=54m or v1=3h
12s - 12 seconds
54m - 54 minutes
3h - 3 hour
I have to write a script in such a way that it whenever v1 is in minutes,
I should strip "m"... (14 Replies)
I need to remove double quoted strings from specific lines in a file. The specific line numbers are a variable. For example, line 5 of the file contains
A B C "string"
I want to remove "string". The following sed command works:
sed '5 s/\"*\"//' $file
If there are multiple... (2 Replies)
Hi All,
I have a file test.txt.
Content of test.txt :
1 vinay se
2 kumar sse
4 kishore tl
I am extracting the content of file with below command.
awk '$2 ~ "vinay" {print $0}' test.txt
Now instead of hardcoding $2 is there any way pass $2 as variable and compare with a... (7 Replies)
Hi,
I am wanting to create a script that will construct a SQL statement based on a a space delimited string that it read from a config file.
Example of the SQL will be
For example, it will read a string like "AAA BBB CCC" and assign to a variable named IN_STRING.
I then concatenate... (2 Replies)
I have two files, file1 and file2 who have identical number of rows and columns. However, the script is supposed to be used for for different files and I cannot know the format in advance. Also, the number of columns changes within the file, some rows have more and some less columns (they are... (13 Replies)
Discussion started by: maya3
13 Replies
LEARN ABOUT CENTOS
unbuffer
UNBUFFER(1) General Commands Manual UNBUFFER(1)NAME
unbuffer - unbuffer output
SYNOPSIS
unbuffer program [ args ]
INTRODUCTION
unbuffer disables the output buffering that occurs when program output is redirected from non-interactive programs. For example, suppose
you are watching the output from a fifo by running it through od and then more.
od -c /tmp/fifo | more
You will not see anything until a full page of output has been produced.
You can disable this automatic buffering as follows:
unbuffer od -c /tmp/fifo | more
Normally, unbuffer does not read from stdin. This simplifies use of unbuffer in some situations. To use unbuffer in a pipeline, use the
-p flag. Example:
process1 | unbuffer -p process2 | process3
CAVEATS
unbuffer -p may appear to work incorrectly if a process feeding input to unbuffer exits. Consider:
process1 | unbuffer -p process2 | process3
If process1 exits, process2 may not yet have finished. It is impossible for unbuffer to know long to wait for process2 and process2 may
not ever finish, for example, if it is a filter. For expediency, unbuffer simply exits when it encounters an EOF from either its input or
process2.
In order to have a version of unbuffer that worked in all situations, an oracle would be necessary. If you want an application-specific
solution, workarounds or hand-coded Expect may be more suitable. For example, the following example shows how to allow grep to finish pro-
cessing when the cat before it finishes first. Using cat to feed grep would never require unbuffer in real life. It is merely a place-
holder for some imaginary process that may or may not finish. Similarly, the final cat at the end of the pipeline is also a placeholder
for another process.
$ cat /tmp/abcdef.log | grep abc | cat
abcdef
xxxabc defxxx
$ cat /tmp/abcdef.log | unbuffer grep abc | cat
$ (cat /tmp/abcdef.log ; sleep 1) | unbuffer grep abc | cat
abcdef
xxxabc defxxx
$
BUGS
The man page is longer than the program.
SEE ALSO
"Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Programs" by Don Libes, O'Reilly and Associates, January 1995.
AUTHOR
Don Libes, National Institute of Standards and Technology
1 June 1994 UNBUFFER(1)