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Top Forums UNIX for Dummies Questions & Answers How do you wait for command substitution processes to complete? Post 302398042 by drl on Tuesday 23rd of February 2010 05:40:43 PM
Old 02-23-2010
Hi.

You seem to be effectively doing:
Code:
zcat $FILE | wc ; echo "HELLO"

I suggest eliminating the tee, since you are throwing away the output from the zcat anyway ( >/dev/null ).

The FIFO that the shell creates for ">(" may be causing the problem. I did verify that the behaviour you posted is accurate -- at least it is with bash and ksh (and it surprised me). It seemed to work correctly with zsh, so you may wish to try that variant.

I didn't quite understand the bigger picture you described, so I cannot comment farther.

Best wishes ... cheers, drl
 

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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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