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Top Forums UNIX for Dummies Questions & Answers Faster than nested while read loops? Post 302545791 by jim mcnamara on Tuesday 9th of August 2011 01:52:28 PM
Old 08-09-2011
The fastest way, arguably, to read a file is process substitutuion in bash, ksh, or zsh.

Code:
a=$(< filename)
b=$(< filename2)

But based on his example and output it looks like he is pasting.
 

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getusershell(3C)					   Standard C Library Functions 					  getusershell(3C)

NAME
getusershell, setusershell, endusershell - get legal user shells SYNOPSIS
#include <unistd.h> char *getusershell(void); void setusershell(void); void endusershell(void); DESCRIPTION
The getusershell() function returns a pointer to a legal user shell as defined by the system manager in the file /etc/shells. If /etc/shells does not exist, the following locations of the standard system shells are used in its place: /bin/bash /bin/csh /bin/jsh /bin/ksh /bin/pfcsh /bin/pfksh /bin/pfsh /bin/sh /bin/tcsh /bin/zsh /sbin/jsh /sbin/pfsh /sbin/sh /usr/bin/bash /usr/bin/csh /usr/bin/jsh /usr/bin/ksh /usr/bin/pfcsh /usr/bin/pfksh /usr/bin/pfsh /usr/bin/sh /usr/bin/tcsh /usr/bin/zsh /usr/xpg4/bin/sh The getusershell() function opens the file /etc/shells, if it exists, and returns the next entry in the list of shells. The setusershell() function rewinds the file or the list. The endusershell() function closes the file, frees any memory used by getusershell() and setusershell(), and rewinds the file /etc/shells. RETURN VALUES
The getusershell() function returns a null pointer on EOF. BUGS
All information is contained in memory that may be freed with a call to endusershell(), so it must be copied if it is to be saved. SunOS 5.10 30 Aug 2004 getusershell(3C)
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