changing col(1) command stdout as fully buffered?


 
Thread Tools Search this Thread
Operating Systems HP-UX changing col(1) command stdout as fully buffered?
# 1  
Old 06-09-2006
changing col(1) command stdout as fully buffered?

Hi All,

I am talking about unix col(1) command used for some reverse line filtering etc.
And I notice that the stdout of this command is line buffered i.e. the stdout will flush the data in its buffer line by line. So the number of writes performed by stdout are more.

So now if I make stdout as fully buffered it will reduce the write hits. Smilie

But if I do these changes I think there will some problems
-> when slow terminals use col(1) as command , then the turn around time will get reduce for it self.
eg: cat file | col -b | lp
Here lp will receive data in terms of buffer size but before it was receving in terms of each lines.

So can I change change col(1) command's stdout to fully buffered?

So do any of you know some more problems related with this change , and can I see some link about col(1) command design stating that it should be either line buffered or fully buffered etc.


Waiting for positive replay,
Sunil kumar.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

awk command 2nd col remove the '-' value

Hi, i was tried using the awk command for replacing '-' in the second column. but the below command replacing the entire file. cat 1.txt |awk '{gsub(/-/,"")}1' Input file 1,2,3,-4,5,6 1,-2,3,4,5,-6 1,2,3,4,5,6 1,-2,3,4,-5,6 Output file 1,2,3,-4,5,6 1,2,3,4,5,-6 1,2,3,4,5,6... (3 Replies)
Discussion started by: onesuri
3 Replies

2. Shell Programming and Scripting

Redirecting stdion, stdout within an AT command

Hello, I'm strugling with some redirecting and all help is apreciated. The following program is working as expected, but the result of the AT command doesn't go to any file. Thanks in advance for the help. #!/bin/bash modem=/dev/ttyUSB1 file=/root/imsi.txt # print error to stderr and exit... (4 Replies)
Discussion started by: cleitao
4 Replies

3. Shell Programming and Scripting

Modifying col values based on another col

Hi, Please help with this. I have several excel files (with and .xlsx format) with 10-15 columns each. They all have the same type of data but the columns are not ordered in the same way. Here is a 3 column example. What I want to do add the alphabet from column 2 to column 3, provided... (9 Replies)
Discussion started by: newbie83
9 Replies

4. Shell Programming and Scripting

Printing from col x to end of line, except last col

Hello, I have some tab delimited data and I need to move the last col. I could hard code it, awk '{ print $1,$NF,$2,$3,$4,etc }' infile > outfile but it would be nice to know the syntax to print a range cols. I know in cut you can do, cut -f 1,4-8,11- to print fields 1,... (8 Replies)
Discussion started by: LMHmedchem
8 Replies

5. UNIX for Advanced & Expert Users

Print line based on highest value of col (B) and repetion of values in col (A)

Hello everyone, I am writing a script to process data from the ATP world tour. I have a file which contains: t=540 y=2011 r=1 p=N409 t=540 y=2011 r=2 p=N409 t=540 y=2011 r=3 p=N409 t=540 y=2011 r=4 p=N409 t=520 y=2011 r=1 p=N409 t=520 y=2011 r=2 p=N409 t=520 y=2011 r=3 p=N409 The... (4 Replies)
Discussion started by: imahmoud
4 Replies

6. Shell Programming and Scripting

redirecting to stdout in betwen command

can anyone help me in making singleline command for Capital Letters are folders ,small letter are files X,Y,Z are subfolders of A as shown below A - X,Y,Z Folder X has three files a.txt,b.txt,c.txt similarly Y,Z. as shown below X- a.txt,b.txt,c.txt Y- a.txt,b.txt,c.txt Z-... (4 Replies)
Discussion started by: phoenix_nebula
4 Replies

7. Programming

Changing STDOUT during runtime

Hi, Currently my STDOUT is configured as tty0, Is there a way to change it during runtime? I need to use this serial for other external device Thanks, Alex (2 Replies)
Discussion started by: alex889
2 Replies

8. UNIX for Dummies Questions & Answers

Info about col command

Hello every1. Can any1 help me with the col command. Wat is a reverse line feed. Which kind of files u need to use the col command. (2 Replies)
Discussion started by: rahulrathod
2 Replies

9. UNIX for Advanced & Expert Users

changing col(1) command stdout as fully buffered?

Hi All, I am talking about unix col(1) command used for some reverse line filtering etc. And I notice that the stdout of this command is line buffered i.e. the stdout will flush the data in its buffer line by line. So the number of writes performed by stdout are more. So now if I make stdout... (0 Replies)
Discussion started by: sunilsbjoshi
0 Replies

10. UNIX for Advanced & Expert Users

Help On col command

Hello Can Any1 tell me the difference between the col command and the col command with the -f option. I tried running both of them but i can't see any difference. Please guide me. (1 Reply)
Discussion started by: rahulrathod
1 Replies
Login or Register to Ask a Question
col(1)							      General Commands Manual							    col(1)

Name
       col - filter reverse line feeds

Syntax
       col [-options]

Description
       The command reads the standard input and writes the standard output.  It performs the line overlays implied by reverse line feeds (ESC-7 in
       ASCII) and by forward and reverse half line feeds (ESC-9 and ESC-8, respectively).  The command is particularly useful for filtering multi-
       column output made with the command of and for filtering output resulting from the preprocessor.

       Although  accepts half line motions in its input, it does not normally output them.  Instead, text that would appear between lines is moved
       to the next lower full line boundary.

       The control characters SO (ASCII code 017) and SI (ASCII code 016) are assumed to start and end text in an alternate  character	set.   The
       character  set (primary or alternate) associated with each printing character read is remembered.  On output, SO and SI characters are gen-
       erated where necessary to maintain the correct treatment of each character.

       The command normally converts white space to tabs to shorten printing time.  If the -h option is given, this conversion is suppressed.

       On input, the only control characters accepted are <space>, <backspace>, <tab>, <return>, <newline>, etc...  The VT character is an  alter-
       nate  form  of  full reverse linefeed, included for compatibility with earlier programs of this type. All other non-printing characters are
       ignored.

Options
       -b     Assumes that the output device does not have backspacing.

       -f     Suppresses moving half lines to the next full line.

       -h     Suppresses conversion of white space to tabs.

       -p     Forces through unchanged any unknown escape sequences that are found in its input. This option should be used with care.

       -x     Suppresses conversion of white space to tabs (same as -h).

Restrictions
       Cannot back up more than 128 lines.
       No more than 800 characters, including backspaces, on a line.

See Also
       tbl(1), nroff(1)

																	    col(1)