simplest way to copy and rename all *.a files to *.b   ???

    simplest way to copy and rename all *.a files to *.b   ???

Different people will have different answers.  What I do is:

rename.pl 's/a$/b/' *.a

where rename.pl is the appended Perl script (it exists in many versions
around the net).  This version is slightly modified by me from lwall's
original to print the successful renames.

karl

#!/usr/bin/env perl
# print changes --karl
#
# Revision 4.0  91/03/20  01:11:53  lwall
# 4.0 baseline.
#
# Revision 3.0.1.2  90/08/09  03:17:57  lwall
# patch19: added man page for relink and rename
'di';
'ig00';

($op = shift) || die "Usage: rename perlexpr [filenames]\n";
if (!@ARGV) {
    @ARGV = <STDIN>;
    chop(@ARGV);

for (@ARGV) {
    $was = $_;
    eval $op;
    die $@ if $@;
    unless ($was eq $_) {
      if (-e $_) {
        warn "rename: skipping $was to $_, already exists\n";
        next;
      }
      print "$was -> $_\n";
      rename($was,$_)
      || warn "rename($was->$_) failed: $!";
    }
########################################################################### ###

        # These next few lines are legal in both Perl and nroff.

.00;                    # finish .ig

'di                     \" finish diversion--previous line must be blank
.nr nl 0-1              \" fake up transition to first page again
.nr % 0                 \" start at page 1
';<<'.ex'; #__END__ ############# From here on it's a standard manual page ############
.TH RENAME 1 "July 30, 1990"
.AT 3
.SH NAME
rename \- renames multiple files
.SH SYNOPSIS
.B rename perlexpr [files]
.SH DESCRIPTION
.I Rename
renames the filenames supplied according to the rule specified as the
first argument.
The argument is a Perl expression which is expected to modify the $_
string in Perl for at least some of the filenames specified.
If a given filename is not modified by the expression, it will not be
renamed.
If no filenames are given on the command line, filenames will be read
via standard input.
.PP
For example, to rename all files matching *.bak to strip the extension,
you might say
.nf

        rename 's/\e.bak$//' *.bak

.fi
To translate uppercase names to lower, you'd use
.nf

        rename 'y/A-Z/a-z/' *

.fi
.SH ENVIRONMENT
No environment variables are used.
.SH FILES
.SH AUTHOR
Larry Wall
.SH "SEE ALSO"
mv(1)
.br
perl(1)
.SH DIAGNOSTICS
If you give an invalid Perl expression you'll get a syntax error.
.SH BUGS
.I Rename
does not check for the existence of target filenames, so use with care.
.ex

Thanks,
I ended up using make to do the job since I am compiling now anyway.
This is under cygwin and I don't want to install another 5MB just to
rename some files.

I am really surprised it can't be done easily with cp, since with DOS
its just copy *.c *.o.

The paradigm used by Unix-like systems is different than used by
DOS-like system.  While the DOS copy command may make this particular
task easy the Unix shell makes other things easy.

On DOS the commands receive those wildcards "*.c" and "*.o" as
arguments and do the filename matching within the program.  But on
Unix the command line shell expands those into file names and populate
the program argument array with expanded versions of the command prior
to handing it to the program.

For example one of the alternatives to using perl 'rename' script
would be to use the shell to loop over the files and rename them in a
loop.

  for f in *.a; do mv -v "$f" "${f%.a}.b" ; done

Or perhaps even this:

  for f in *.a; do echo mv "$f" "${f%.a}.b" ; done | sh -x

Bob

Thanks, exactly what I wanted. I'll have to add those to my linux cheat
sheet.