Sponsored Content
Top Forums Shell Programming and Scripting Questions about file descriptors Post 302917476 by solaris_user on Wednesday 17th of September 2014 02:59:27 AM
Old 09-17-2014
Questions about file descriptors

Hi, I'm playing with KSH

I entered following command in terminal

Code:
{ echo "stdout" >&1; echo "stderr" >&2; } > out

And I get only stoud in a new file out.

My question is: Where did my stderr vanish ?
 

10 More Discussions You Might Find Interesting

1. Programming

File Descriptors

Hi, I have written a daemon process, to perform certain operations in the background. For this I have to close, the open file descriptors, Does anybody know how to find out the number of open file descriptors ? Thanks in Advance, Sheetal (2 Replies)
Discussion started by: s_chordia
2 Replies

2. UNIX for Advanced & Expert Users

File Descriptors

Hello all, A few questions on file descriptors ... scenario : Sun Ultra 30 with Sun OS 5.5.1 , E250 with Solaris 2.6 In one of my servers, the file descriptor status from the soft limit and hard limits are 64 and 1024 respectively for root user. Is the soft limit (64) represents the... (3 Replies)
Discussion started by: shibz
3 Replies

3. UNIX for Dummies Questions & Answers

file descriptors

i m trying to learn processes in unix and i've been reading this but i don't quite get it. its regarding file descriptors. : each is a part of file pointers, they point to another area. indexes into an Operating system maintained table called "file descriptor table". one table per process. may... (3 Replies)
Discussion started by: a25khan
3 Replies

4. Shell Programming and Scripting

Multiple co-processor file descriptors

I have a script that creates a KSH co-process for Oracle sqlplus and I am presently interacting with it via print -p and read -p. I also need to interact with another Oracle database what isn't permitted to have any direct connection to the first. Presently, I simply disconnect from the first... (10 Replies)
Discussion started by: tmarikle
10 Replies

5. Programming

Sockets and File descriptors

I am in a Systems programming class this semester, and our current project is to write a program utilizing sockets and fork. For the project, I decided to make my own instant messaging program. I have the code completed, but I have a problem that keeps old clients from communicating with new... (3 Replies)
Discussion started by: gstlouis
3 Replies

6. UNIX for Advanced & Expert Users

File descriptors missing on startup

Dec 20 15:34:32 hostname sendmail: File descriptors missing on startup: stderr; Bad file number Dec 20 15:34:32 hostname sendmail: File descriptors missing on startup: stderr; Bad file number Dec 20 15:34:32 hostname sendmail: File descriptors missing on startup: stderr; Bad file number Dec... (1 Reply)
Discussion started by: xnightcrawl
1 Replies

7. UNIX for Advanced & Expert Users

File Descriptors + cron

Hi All, This thread is going to be a discussion basically bringing out more information from the experts on cron jobs and the associated file handles. So, here is the question. There is definitely a constant ' n ' as the maximum number of file handles alloted to a process ' p '. Will... (7 Replies)
Discussion started by: matrixmadhan
7 Replies

8. UNIX for Dummies Questions & Answers

Using File Descriptors, traverse a list

I have written this code, and according to my research it SHOULD be going down the list until it is finished, but I am getting blank feedback. Nothing is being output as far as I can tell. #!/bin/sh while echo Enter to start traversing read enter do read list <&3 echo $list done any... (2 Replies)
Discussion started by: MaestroRage
2 Replies

9. HP-UX

exec and file descriptors

Hi, I speak and write english more or less, so I hope my asking be clear. :) In the company I am working, they are using control-m software to lunch shell scripts. So i put this command in all shell scripts: export LOGFILE_tmp=$PRODUC_DATA/tmp/${SCRIPT}_${PAIS}_`date... (0 Replies)
Discussion started by: anamcara
0 Replies

10. UNIX for Dummies Questions & Answers

Semaphores and File Descriptors

What is the difference between a file descriptor and a semaphore? My basic understanding is: - a file descriptor is a small positive integer that the system uses instead of the file name to identify an open file or socket. - a semaphore is a variable with a value that indicates the... (1 Reply)
Discussion started by: Mr_Webster
1 Replies
tabs(1) 						      General Commands Manual							   tabs(1)

NAME
tabs - set tabs on a terminal SYNOPSIS
[tabspec] n] type] DESCRIPTION
sets the tab stops on the user's terminal according to the tab specification tabspec, after clearing any previous settings. The user's terminal must have remotely-settable hardware tabs. If you are using a non-HP terminal, you should keep in mind that behavior will vary for some tab settings. Four types of tab specification are accepted for tabspec: ``canned'', repetitive, arbitrary, and file. If no is given, the default value is i.e., UNIX ``standard'' tabs. The lowest column number is 1. Note that for tabs, column 1 always refers to the left-most column on a terminal, even one whose column markers begin at 0. Gives the name of one of a set of ``canned'' tabs. Recognized codes and their meanings are as follows: 1,10,16,36,72 Assembler, IBM S/370, first format 1,10,16,40,72 Assembler, IBM S/370, second format 1,8,12,16,20,55 COBOL, normal format 1,6,10,14,49 COBOL compact format (columns 1-6 omitted). Using this code, the first typed character corresponds to card column 7, one space gets you to column 8, and a tab reaches column 12. Files using this tab setup should have specify a format specification file as defined by below. The file should have the following format specification: 1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67 COBOL compact format (columns 1-6 omitted), with more tabs than This is the recommended format for COBOL. The appro- priate format specification is: 1,7,11,15,19,23 FORTRAN 1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61 PL/I 1,10,55 SNOBOL 1,12,20,44 UNIVAC 1100 Assembler In addition to these ``canned'' formats, three other types exist: A repetitive specification requests tabs at columns 1+n, 1+2xn, etc. Of particular importance is the value this represents the UNIX ``standard'' tab setting, and is the most likely tab setting to be found at a terminal. Another special case is the value implying no tabs at all. The arbitrary format permits the user to type any chosen set of numbers, separated by commas, in ascending order. Up to 40 numbers are allowed. If any number (except the first one) is preceded by a plus sign, it is taken as an increment to be added to the previous value. Thus, the tab lists 1,10,20,30 and 1,10,+10,+10 are considered identical. If the name of a file is given, reads the first line of the file, searching for a format specification. If it finds one there, it sets the tab stops according to it, otherwise it sets them as This type of specification can be used to ensure that a tabbed file is printed with correct tab settings, and is suitable for use with the command (see pr(1)): Any of the following can be used also; if a given option occurs more than once, the last value given takes effect: usually needs to know the type of terminal in order to set tabs and always needs to know the type to set margins. type is a name listed in term(5). If no option is supplied, searches for the value in the environment (see environ(5)). If is not defined in the environment, tries a sequence that will work for many terminals. The margin argument can be used for some terminals. It causes all tabs to be moved over n columns by making column n+1 the left margin. If is given without a value of n, the value assumed is 10. The normal (left-most) margin on most terminals is obtained by The margin for most terminals is reset only when the option is given explicitly. Tab and margin setting is performed via the standard output. EXTERNAL INFLUENCES
Environment Variables determines the interpretation of text within file as single- and/or multi-byte characters. determines the language in which messages are displayed. If or is not specified in the environment or is set to the empty string, the value of is used as a default for each unspecified or empty variable. If is not specified or is set to the empty string, a default of "C" (see lang(5)) is used instead of If any internationalization variable contains an invalid setting, behaves as if all internationalization variables are set to "C". See environ(5). International Code Set Support Single- and multi-byte character code sets are supported. DIAGNOSTICS
Arbitrary tabs are ordered incorrectly. A zero or missing increment found in an arbitrary specification. A ``canned'' code cannot be found. option was used and file cannot be opened. option was used and the specification in that file points to yet another file. Indirection of this form is not permitted. WARNINGS
There is no consistency among different terminals regarding ways of clearing tabs and setting the left margin. It is generally impossible to usefully change the left margin without also setting tabs. clears only 20 tabs (on terminals requiring a long sequence), but is willing to set 64. SEE ALSO
nroff(1), pr(1), tset(1), environ(5), term(5). STANDARDS CONFORMANCE
tabs(1)
All times are GMT -4. The time now is 04:53 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy