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Top Forums UNIX for Advanced & Expert Users [Discussion] POSIX, the Love of Backticks and All That Jazz Post 302990658 by Peasant on Monday 30th of January 2017 10:49:20 AM
Old 01-30-2017
Lets not get deep into subshells.

I'm sure you experts don't have too many nested subshells in your code Smilie
In my opinion, it lowers the control you have in your program.

So if you have small, efficient script with no nested subshells, are backquotes still the lowest denominator e.g will it run without magic cookie on any unix OS ever produced ?

Example would be a simple mv script using basename command in subshell.
 

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basename(1)						      General Commands Manual						       basename(1)

Name
       basename - strip directory names from pathname

Syntax
       basename string [ suffix ]

Description
       The  command  deletes from string any prefix up to and including the last slash (/) and the suffix (if specified), and prints the result on
       the standard output.  The command handles limited regular expressions in the same manner as metacharacters must	be  escaped  if  they  are
       intended to be interpreted literally.  For example:
       % basename /vmunix .x
       vmun
       % basename /vmunix '.x'
       vmunix
       In  the	first example, returns because it interprets the as a regular expression consisting of any character followed by the letter In the
       second example, the dot is escaped; there is no match on a dot followed by and returns

       The command is often used inside substitution marks (` `) within shell procedures.

Examples
       The following example shell script compiles the file and moves the output to in the current directory:
       cc /usr/src/bin/cat.c
       mv a.out `basename $1 .c`
       The following example echoes only the base name of the file by removing the prefix and any possible sequence of	characters  following  the
       period in the file's name:
       % basename /etc/syslog.conf '..*'
       syslog

See Also
       dirname(1), ex(1), sh(1)

																       basename(1)
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