03-22-2001
UNIX commands
Thanks for the hint PxT. I tried the "whereis gunzip" command, and "gunzip:" appeared on the next line. What does that mean? Thanks in advance!
Carrmen
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Where can I get a list of basic commands ? I want to get up to speed as soon as possible ? thanks..... (4 Replies)
Discussion started by: drukkie
4 Replies
2. UNIX for Dummies Questions & Answers
I want to know if there is a way to send unix commands thru FTP from a mainframe to kick off Autosys Jobs. I just need to send a command from the mainframe to UNIX and have UNIX execute that command. (2 Replies)
Discussion started by: skammer
2 Replies
3. UNIX for Dummies Questions & Answers
I would be happy to streamline some of the commands I am trying to learn with easy to remember terms, like dir for ls -l. I am wondering if you script certain commands for every time you start-up your system, can use those aliases there? If so, would that prove a problem for administrators who... (2 Replies)
Discussion started by: wmosley2
2 Replies
4. HP-UX
HP 9000/800 Server running HP-UX UNIX Server, users are connected via LAN and dialup connection.
Need help to write SHELL SCRIPT or UNIX Commands which would perform the following:
-ping IP address of all login/connected users to our server
-send customized text message to all the login... (1 Reply)
Discussion started by: Moinul Haque
1 Replies
5. UNIX Desktop Questions & Answers
What is the unix command that will display the current UTC time, hours, and minutes only.
What is the unix command for sorting in descending order.
What is the unix command for display the first 10 characters in a file. (4 Replies)
Discussion started by: charlton
4 Replies
6. UNIX for Dummies Questions & Answers
I am able to run the UNIX commands in a Windows box from a UNIX box through "SSH" functionality. But whenever the SSH connection is established between UNIX and Windows, password for windows box is being asked.
Is there a way to avoid asking password whenever the SSH connection is made? Can I... (1 Reply)
Discussion started by: D.kalpana
1 Replies
7. UNIX for Dummies Questions & Answers
i want to know how to do a few things using unix commands.
firstly say I have a .txt file that contains random lines like
Hello
Goodbye
I'm tired
5
74
using the grep command how can I get a list of lines that contain ONLY digits?
also using pipes to combine ls and grep commands how... (5 Replies)
Discussion started by: ez45
5 Replies
8. UNIX for Dummies Questions & Answers
Hello Folks
Where can I find all the unix commands with explanations , on the internet. I am searching but most of the sites are listing a few of the important ones. PLease guide through
thanks (4 Replies)
Discussion started by: supercops
4 Replies
9. UNIX for Dummies Questions & Answers
What are the various commands which use $ in unix and what do each of these indicate? eg: echo $? returns the success status of the previous commands..similarly $$ returns some numeric value..wat exactly are these?
From where can a download a document which can help me getting more details about... (2 Replies)
Discussion started by: DDS
2 Replies
10. UNIX for Dummies Questions & Answers
Having trouble doing the following things, I know it has something to do with using metacharacters but I'm not able to get it working correctly.
I need a command to get a long directory listing of all the files that have:
exactly two characters following the letters zot.
all files that... (1 Reply)
Discussion started by: lakers34kb
1 Replies
LEARN ABOUT MOJAVE
perlio::gzip
gzip(3) User Contributed Perl Documentation gzip(3)
NAME
PerlIO::gzip - Perl extension to provide a PerlIO layer to gzip/gunzip
SYNOPSIS
use PerlIO::gzip;
open FOO, "<:gzip", "file.gz" or die $!;
print while <FOO>; # And it will be uncompressed...
binmode FOO, ":gzip(none)" # Starts reading deflate stream from here on
DESCRIPTION
PerlIO::gzip provides a PerlIO layer that manipulates files in the format used by the "gzip" program. Compression and Decompression are
implemented, but not together. If you attempt to open a file for reading and writing the open will fail.
EXPORT
PerlIO::gzip exports no subroutines or symbols, just a perl layer "gzip"
LAYER ARGUMENTS
The "gzip" layer takes a comma separated list of arguments. 4 exclusive options choose the header checking mode:
gzip
The default. Expects a standard gzip file header for reading, writes a standard gzip file header.
none
Expects or writes no file header; assumes the file handle is immediately a deflate stream (eg as would be found inside a "zip" file)
auto
Potentially dangerous. If the first two bytes match the "gzip" header "x1fx8b" then a gzip header is assumed (and checked) else a
deflate stream is assumed. No different from gzip on writing.
autopop
Potentially dangerous. If the first two bytes match the "gzip" header "x1fx8b" then a gzip header is assumed (and checked) else the
layer is silently popped. This results in gzip files being transparently decompressed, other files being treated normally. Of course,
this has sides effects such as File::Copy becoming gunzip, and File::Compare comparing the uncompressed contents of files.
In autopop mode Opening a handle for writing (or reading and writing) will cause the gzip layer to automatically be popped.
Optionally you can add this flag:
lazy
For reading, defer header checking until the first read. For writing, don't write a header until the first buffer empty of compressed
data to disk. (and don't write anything at all if no data was written to the handle)
By default, gzip header checking is done before the "open" (or "binmode") returns, so if an error is detected in the gzip header the
"open" or "binmode" will fail. However, this will require reading some data, or writing a header. With lazy set on a file opened for
reading the check is deferred until the first read so the "open" should always succeed, but any problems with the header will cause an
error on read.
open FOO, "<:gzip(lazy)", "file.gz" or die $!; # Dangerous.
while (<FOO>) {
print;
} # Whoa. Bad. You're not distinguishing between errors and EOF.
If you're not careful you won't spot the errors - like the example above you'll think you got end of file.
lazy is ignored if you are in autopop mode.
AUTHOR
Nicholas Clark, <nwc10+perlio-gzip@colon.colondot.net>
SEE ALSO
perl, gzip, rfc 1952 <http://www.ietf.org/rfc/rfc1952.txt> (the gzip file format specification), rfc 1951
<http://www.ietf.org/rfc/rfc1951.txt> (DEFLATE compressed data format specification)
perl v5.18.2 2006-10-01 gzip(3)