You can use the xargs utility to feed arguments from lines into commands that take arguments. echo a b c | xargs cat is equivalent to cat a b c for example.
If your filenames contain spaces, this may be insufficient, and solutions would be system-dependent. On GNU/Linux you could do
Hi all, quick question...
Im trying to configure Redhat 9 to dial out to my ISP AOL. I have found some software to do this but at present I can't get net access under Linux for the reason stated. I can however acces the net using my laptop running windows.
The question is:
I have downloaded... (3 Replies)
I have a file of type .for extension .In a guui based unix environment like solaris if I double click on that file a specific program designed by me has to run which takes this file as the parameter and exceutes the program.
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Hey y'all,
I need some help with the nitty gritty of the ls command.
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I am trying to write a script and failing miserably. I have a file that looks something like this;
20050924-155819;Backoffice;1037;0;DDT-TCP/IP;;0;Node
20050924-155902;Unknown;1036;0;DDT-TCP/IP;;0;Node
20050924-155922;FrontOffice;1040;5;DDT-
The desired result is one file containing only... (4 Replies)
Now that I have a file that looks something like this;
20050926 Unknown
20050926 MUREXFO
20050926 MUREXFO
20050926 MUREXFO
20050926 Unknown
20050926 KADDUSS
20050926 KADDUSS
20050926 KADDUSS
20050926 MUREXFO
Is there a way in vi that I can search the file and remove any line... (2 Replies)
I'm trying to create a simple file inventory for a series of huge directories containing e-records. What I'm after is a list of all directories and sub-directories with just the number of each type of file in that directory/sub-directory. For example output would look like:
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Hello,
I have several thousand files with different extensions in a directory. Is there a single command to get what the various extensions are with a single command.
Thanks for your help!
Best,
Guss (2 Replies)
Hi guys,
I have just been bothered by a fairly small issue for some time now. I am trying to search (using find -name) for some .jpg files recursively. This is a Redhat environment with bash.
I get this job done though I need to copy ALL of them and put them in a separate folder BUT I also... (1 Reply)
the following excludes certain directories successfully
cp -r probe/!(dir) /destination
I want to exclude certain file types and tried unsuccessfully
cp -r probe/!(*.avi) /destination (2 Replies)
Discussion started by: tmf
2 Replies
LEARN ABOUT PLAN9
rl
rl(1) User Commands rl(1)NAME
rl - Randomize Lines.
SYNOPSIS
rl [OPTION]... [FILE]...
DESCRIPTION
rl reads lines from a input file or stdin, randomizes the lines and outputs a specified number of lines. It does this with only a single
pass over the input while trying to use as little memory as possible.
-c, --count=N
Select the number of lines to be returned in the output. If this argument is omitted all the lines in the file will be returned in
random order. If the input contains less lines than specified and the --reselect option below is not specified a warning is printed
and all lines are returned in random order.
-r, --reselect
When using this option a single line may be selected multiple times. The default behaviour is that any input line will only be
selected once. This option makes it possible to specify a --count option with more lines than the file actually holds.
-o, --output=FILE
Send randomized lines to FILE instead of stdout.
-d, --delimiter=DELIM
Use specified character as a "line" delimiter instead of the newline character.
-0, --null
Input lines are terminated by a null character. This option is useful to process the output of the GNU find -print0 option.
-n, --line-number
Output lines are numbered with the line number from the input file.
-q, --quiet, --silent
Be quiet about any errors or warnings.
-h, --help
Show short summary of options.
-v, --version
Show version of program.
EXAMPLES
Some simple demonstrations of how rl can help you do everyday tasks.
Play a random sound after 4 minutes (perfect for toast):
sleep 240 ; play `find /sounds -name '*.au' -print | rl --count=1`
Play the 15 most recent .mp3 files in random order.
ls -c *.mp3 | head -n 15 | rl | xargs --delimiter='
' play
Roll a dice:
seq 6 | rl --count 2
Roll a dice 1000 times and see which number comes up more often:
seq 6 | rl --reselect --count 1000 | sort | uniq -c | sort -n
Shuffle the words of a sentence:
echo -n "The rain in Spain stays mainly in the plain."
| rl --delimiter=' ';echo
Find all movies and play them in random order.
find . -name '*.avi' -print0 | rl -0 | xargs -n 1 -0 mplayer
Because -0 is used filenames with spaces (even newlines and other unusual characters) in them work.
BUGS
The program currently does not have very smart memory management. If you feed it huge files and expect it to fully randomize all lines it
will completely read the file in memory. If you specify the --count option it will only use the memory required for storing the specified
number of lines. Improvements on this area are on the TODO list.
The program uses the rand() system random function. This function returns a number between 0 and RAND_MAX, which may not be very large on
some systems. This will result in non-random results for files containing more lines than RAND_MAX.
Note that if you specify multiple input files they are randomized per file. This is a different result from when you cat all the files and
pipe the result into rl.
COPYRIGHT
Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Arthur de Jong.
This is free software; see the license for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Version 0.2.7 Jul 2008 rl(1)