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Top Forums Shell Programming and Scripting Script to change first line of files in directory Post 302653579 by agama on Saturday 9th of June 2012 02:06:15 PM
Old 06-09-2012
Quote:
Originally Posted by alister
Perhaps this will meet your needs:
Code:
cd "$1"
for f in *; do
    [ ! -f "$f" ] && continue
    if [ -s "$f" ]; then
        printf %s\\n 1c "$f" . w q | ed -s "$f"
    else
        printf %s\\n "$f" > "$f"
    fi
done

I would suggest one small change: add some error checking to the cd command. If the user mistypes the path, it will work on all files in the current directory which is probably not what is intended.

Code:
if ! cd "${1:-no-such-directory}"     # also quote on the off chance that something in the path has spaces
then
   echo "abort: could not switch to '$1' or parameter was missing"
   exit 1
fi

 

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DH_INSTALLDEB(1)						     Debhelper							  DH_INSTALLDEB(1)

NAME
dh_installdeb - install files into the DEBIAN directory SYNOPSIS
dh_installdeb [debhelperoptions] DESCRIPTION
dh_installdeb is a debhelper program that is responsible for installing files into the DEBIAN directories in package build directories with the correct permissions. FILES
package.postinst package.preinst package.postrm package.prerm These maintainer scripts are installed into the DEBIAN directory. Inside the scripts, the token #DEBHELPER# is replaced with shell script snippets generated by other debhelper commands. package.triggers package.shlibs These control files are installed into the DEBIAN directory. Note that package.shlibs is only installed in compat level 9 and earlier. In compat 10, please use dh_makeshlibs(1). package.conffiles This control file will be installed into the DEBIAN directory. In v3 compatibility mode and higher, all files in the etc/ directory in a package will automatically be flagged as conffiles by this program, so there is no need to list them manually here. package.maintscript Lines in this file correspond to dpkg-maintscript-helper(1) commands and parameters. However, the "maint-script-parameters" should not be included as debhelper will add those automatically. Example: # Correct rm_conffile /etc/obsolete.conf 0.2~ foo # INCORRECT rm_conffile /etc/obsolete.conf 0.2~ foo -- "$@" In compat 10 or later, any shell metacharacters will be escaped, so arbitrary shell code cannot be inserted here. For example, a line such as "mv_conffile /etc/oldconffile /etc/newconffile" will insert maintainer script snippets into all maintainer scripts sufficient to move that conffile. It was also the intention to escape shell metacharacters in previous compat levels. However, it did not work properly and as such it was possible to embed arbitrary shell code in earlier compat levels. The dh_installdeb tool will do some basic validation of some of the commands listed in this file to catch common mistakes. The validation is enabled as a warning since compat 10 and as a hard error in compat 12. SEE ALSO
debhelper(7) This program is a part of debhelper. AUTHOR
Joey Hess <joeyh@debian.org> 11.1.6ubuntu2 2018-05-10 DH_INSTALLDEB(1)
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