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Full Discussion: awk to use variable instead of stdin or file
Top Forums Shell Programming and Scripting awk to use variable instead of stdin or file Post 302971984 by Don Cragun on Wednesday 27th of April 2016 06:08:54 PM
Old 04-27-2016
Yes, set -- arg... goes way back and is required by the standards. And, if you don't want to set your positional parameters, something else that goes way back and is also required by the standards is read and, if you don't want to use a pipeline to feed it input from echo or printf, here-documents also go way back and are also required by the standards:
Code:
$ JIOO=hello.one.two.three
$ 
$ IFS='.' read var1 var2 leftover <<EOF
$J100
EOF
$ echo "$var1"
hello
$ echo "$var2"
one
$ echo "$leftover"
two.three
$

IFS, read, and here-documents are all part of the shell programming language and never require any external utilities to get the job done (unless, of course, you perform a command substitution in the body of the here-document).

Here-strings (i.e. <<< "string") are recent additions to a few shells and are allowed as an extension to the standards, but are not required by the standards.
 

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LEARN ABOUT OSF1

getpid

getpid(2)							System Calls Manual							 getpid(2)

NAME

       getpid, getpgrp, getppid - Gets the process ID, process group ID, parent process ID

SYNOPSIS

       #include <unistd.h>

       pid_t getpid( void );

       pid_t getpgrp( void );

       pid_t getppid( void );

       Application  developers	may  want  to  specify an #include statement for <sys/types.h> before the one for <unistd.h> if programs are being
       developed for multiple platforms. The additional #include statement is not required on Tru64 UNIX systems or by ISO  or	X/Open	standards,
       but may be required on other vendors' systems that conform to these standards.

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       getpid(), getpgrp(), getppid():	POSIX.1, XPG4, XPG4-UNIX

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

DESCRIPTION

       The getpid() function returns the process ID of the calling process.

       The getpgrp() function returns the process group ID of the calling process.

       The  getppid()  function  returns  the  parent  process ID of the calling process.  When a process is created, its parent process ID is the
       process ID of its parent process.  If a parent process exits, the parent process IDs of its child processes are changed to the  process	ID
       of the init program.

RELATED INFORMATION

       System calls: fork(2), kill(2), setpgid(2), setsid(2), wait(2)

       Standards: standards(5) delim off

																	 getpid(2)
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