10-04-2018
Quote:
Originally Posted by
wisecracker
It is surprising how difficult it is to create code to work on multiple platforms with large time spans between platform types and differences in languages as they evolve over these time spans.
Depends what you're doing. Hardware I/O changes often, plain old data processing hasn't. awk in particular didn't burden itself with 100,000 obsolete expansion modules like Perl and Python did, or changed as much as shell has; it remains a special-purpose language just for data processing, quite portable. Mostly. You can find it on anything from wireless routers on up, but occasionally we must tell people 'use nawk on solaris' or else they'll get a crusty old version backwards-compatible with 1977.
Quote:
It took me a long time to do an FFT for Python 1.4.0 for the A1200, to the current, (04-10-2018), 3.7.0 for current machines, but I got there in the end. Everything is easy when code is written around current language versions but backwards compatibility is hard.
Python is one of the worst languages for backwards compatibility, its basic syntax changes with every sneeze.
Quote:
Once done I will leave the Awk version for you... <wink>
If you're curious, there's a lot more to learn about awk. It's actually a very fast, powerful, and low-footprint language for processing text. (It had to be, to operate on 1977 hardware.) It's not a do-everything language, it has a few really nice features and not a lot else. You wouldn't write a menu system or graphical UI with it. But for data processing it's almost as powerful as perl.
Last edited by Corona688; 10-04-2018 at 01:50 PM..
These 3 Users Gave Thanks to Corona688 For This Post:
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hello All,
Below is a simple script i worte to find the 208th char in a file. If the char = "C" then I re-direct the line to a file called change.txt. If it is not "C" then I re-direct it to a file called delete.txt.
My problem is I have a file 0f 500K lines. this script is very slow. I am... (4 Replies)
Discussion started by: eja
4 Replies
2. Shell Programming and Scripting
Any means of running ksh93 in a ksh88-mode?
Might sound odd, but I want/need to restrict U/Win-developed scripts to correspond to the ksh88 version on my Solaris environment(s). Thanks. (2 Replies)
Discussion started by: curleb
2 Replies
3. Shell Programming and Scripting
Hi all!
Does anybody know how can I check if any UNIX installation has implemented ksh88 or ksh93?
Thanks in advance.
Néstor. (3 Replies)
Discussion started by: Nestor
3 Replies
4. Shell Programming and Scripting
I have a text file that contains 4 million lines, each line contains 2 fields(colon as field separator). as shown:
123:444,555,666,777,888,345
233:5444,555,666,777,888,345
623:454,585,664,773,888,345
......
Here I have to split the second field(can be up to 40,000 fields) by comma into an... (14 Replies)
Discussion started by: kevintse
14 Replies
5. Shell Programming and Scripting
Hi,
I have a script that, basically, has two input files of this type:
file1
key1=value1_1_1
key2=value1_2_1
key4=value1_4_1
...
file2
key2=value2_2_1
key2=value2_2_2
key3=value2_3_1
key4=value2_4_1
...
My files are 10k lines big each (approx).
The keys are strings that don't... (7 Replies)
Discussion started by: fzd
7 Replies
6. Shell Programming and Scripting
Hi,
I have a large number of input files with two columns of numbers.
For example:
83 1453
99 3255
99 8482
99 7372
83 175
I only wish to retain lines where the numbers fullfil two requirements. E.g:
=83
1000<=<=2000
To do this I use the following... (10 Replies)
Discussion started by: s052866
10 Replies
7. UNIX for Advanced & Expert Users
Hi Experts,
I have several shell scripts that have been developed on a Linux box for korn ksh93.
If we want to run this software on an AIX 6.1 box that runs ksh88 by default can we just change the she-bang line to reference /bin/ksh93 which ships with AIX as its "enhanced shell" to ensure... (6 Replies)
Discussion started by: Keith Turley
6 Replies
8. OS X (Apple)
I don't know if anyone is interested but I have been meddling with FFT for the AMIGA.
(Sadly we AMIGAns don't have these luxuries through any scripting language.
Below is a Python snippet that uses the builtin 'cmath' module to work with the lowly
Python 2.0.1 for the AMIGA. It is part of a... (0 Replies)
Discussion started by: wisecracker
0 Replies
9. AIX
Hi everyone !
Im trying to know from wich version of AIX KSH93 is available ?
Internet tell me 6.x and 7.x AIX are available, bue what about 5.x ?
Is KSH93 available on AIX 5.x ?
Is it the same way to manipulate variables as KSH93 on 7.x ?
Thanks for your support and have a nice day ! (2 Replies)
Discussion started by: majinfrede
2 Replies
10. OS X (Apple)
Hi guys...
This is code that was originally designed to work on an upgraded AMIGA A1200 using Python 2.0.x.
Unfortunately it broke inside much later versions, NOT because of the print statement/function but other minor subtleties. So this is the final result tested on various machines including... (0 Replies)
Discussion started by: wisecracker
0 Replies
LEARN ABOUT CENTOS
tpm_quote_tools
TPM QUOTE
TOOLS(8) TPM QUOTE TOOLS(8)
NAME
TPM Quote Tools
PROGRAMS
tpm_mkuuid, tpm_mkaik, tpm_loadkey, tpm_unloadkey, tpm_getpcrhash, tpm_updatepcrhash, tpm_getquote, tpm_verifyquote
DESCRIPTION
TPM Quote Tools is a collection of programs that provide support for TPM based attestation using the TPM quote operation.
A TPM contains a set of Platform Configuration Registers (PCRs). In a well configured machine, some of these registers are set to known
values during the boot up process or at other times. For example, a PCR might contain the hash of a boot loader in memory before it is
run.
The TPM quote operation is used to authoritatively verify the contents of a TPM's Platform Configuration Registers (PCRs). During provi-
sioning, a composite hash of a selected set of PCRs is computed. The TPM quote operation produces a composite hash that can be compared
with the one computed while provisioning.
To use the TPM quote operation, keys must be generated. During provisioning, an Attestation Identity Key (AIK) is generated for each TPM,
and the public part of the key is made available to entities that validate quotes.
The TPM quote operation returns signed data and a signature. The data that is signed contains the PCRs selected for the operation, the
composite hash for the selected PCRs, and a nonce provided as input, and used to prevent replay attacks. At provisioning time, the data
that is signed is stored, not just the composite hash. The signature is discarded.
An entity that wishes to evaluate a machine generates a nonce, and sends it along with the set of PCR used to generate the composite PCR
hash at provisioning time. For this use of the TPM quote operation, the signed data is ignored, and the signature returned is used to val-
idate the state of the TPM's PCRs. Given the signature, the evaluating entity replaces the nonce in the signed data generated at provi-
sioning time, and checks to see if the signature is valid for the data. If so, this check ensures the selected PCRs contain values that
match the ones measured during provisioning.
A typical scenario for an enterprise using these tools follows. The tools expect AIKs to be referenced via one enterprise-wide Universally
Unique Identifier (UUID). The program tpm_mkuuid creates one.
For each machine being checked, an AIK is created using tpm_mkaik. The key blob produced is bound to the UUID on its machine using
tpm_loadkey. The public key associated with the AIK is sent to the entities that verify quotes. Finally, the expected PCR composite hash
is obtained using tpm_getpcrhash. When the expected PCR values change, a new hash can be generated with tpm_updatepcrhash.
The program to obtain a quote, and thus measure the current state of the PCRs is tpm_getquote. The program that verifies the quote
describes the same PCR composite hash as was measured initially is tpm_verifyquote.
SEE ALSO
tpm_mkuuid(8), tpm_mkaik(8), tpm_loadkey(8), tpm_unloadkey(8), tpm_getpcrhash(8), tpm_updatepcrhash(8), tpm_getquote(8), tpm_verifyquote(8)
Oct 2010 TPM QUOTE TOOLS(8)