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Full Discussion: Named pipe hanging?
Top Forums UNIX for Dummies Questions & Answers Named pipe hanging? Post 302893552 by shamrock on Wednesday 19th of March 2014 05:23:57 PM
Old 03-19-2014
Quote:
Originally Posted by Corona688
wc -l < somepipe & will hang in a shell, while wc -l somepipe & will not... The difference is subtle but important: One tells wc -l to open the pipe, which happens after it's run and backgrounded. The other tells the shell to open the pipe, which happens before it's run and backgrounded.
Nope...the only difference is that wc -l somepipe & will give the no. of line plus the filename whereas wc -l < somepipe & will give the no. of lines in the ls -ltr listing...that is just the way wc -l works...
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Corona688
 

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LEARN ABOUT CENTOS

platform::shell

platform::shell(n)					       Tcl Bundled Packages						platform::shell(n)

__________________________________________________________________________________________________________________________________________________

NAME

       platform::shell - System identification support code and utilities

SYNOPSIS

       package require platform::shell ?1.1.4?

       platform::shell::generic shell
       platform::shell::identify shell
       platform::shell::platform shell
_________________________________________________________________

DESCRIPTION

       The platform::shell package provides several utility commands useful for the identification of the architecture of a specific Tcl shell.

       This  package  allows the identification of the architecture of a specific Tcl shell different from the shell running the package. The only
       requirement is that the other shell (identified by its path), is actually executable on the current machine.

       While for most platform this means that the architecture of the interrogated shell is identical to the architecture of  the  running  shell
       this  is  not generally true. A counter example are all platforms which have 32 and 64 bit variants and where a 64bit system is able to run
       32bit code. For these running and interrogated shell may have different 32/64 bit settings and thus different identifiers.

       For applications like a code repository it is important to identify the architecture of the shell which will  actually  run  the  installed
       packages, versus the architecture of the shell running the repository software.

COMMANDS

       platform::shell::identify shell
	      This command does the same identification as platform::identify, for the specified Tcl shell, in contrast to the running shell.

       platform::shell::generic shell
	      This command does the same identification as platform::generic, for the specified Tcl shell, in contrast to the running shell.

       platform::shell::platform shell
	      This command returns the contents of tcl_platform(platform) for the specified Tcl shell.

KEYWORDS

       operating system, cpu architecture, platform, architecture

platform::shell 						       1.1.4							platform::shell(n)
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