sed

gluon · 02-01-2002, 02:53 PM

Hello

I'm looking for a way of transforming file paths with sed. For example, is there a way to transform

/home/gluon/programming/file_db/shell/../java/FileTest.java

into

/home/gluon/programming/file_db/java/FileTest.java

by removing "a_dir/.." ???

I'm really not used to using sed, but I know that removing "../a_dir" is much easier than removing "a_dir/..", but it's really useless for me !!!

Thank you in advance !!!

Gluon

acid_kewpie · 02-01-2002, 03:31 PM

i'd suggest using tr instead of sed, i never could suss out out to deal with /'s in sed...

tr "/shell/.." ""

crabboy · 02-01-2002, 08:42 PM

It's all about escaping characters that would be intrepreted as a regular expression or the delimeter for sed. ( / )

Code:

DIR1="/home/gulon/programming/file_db/shell/../java/FileTest.java"

echo $DIR1 | sed 's/shell\/\.\.\///'

gluon · 02-02-2002, 03:18 AM

acid_kewpie : thank you, but I want to go on with 'sed' ;-)

crabboy : thank you too for your answer ! It works perfectly well but, as I posted this message, I forgot to precise that this script had to work with multi-'..', eg :

transformation of

/home/gluon/programming/file_db/shell/../../system/ccp.c

into

/home/gluon/programming/system/ccp.c

It could be something like 'recursive', ie crunching every 'dir/..' patern until the desired path hasn't any anymore.

I really hope that you'll be able to help me : I've already spent about 5 days on that problem !!!

Thanks in advance and CU

:smash:

crabboy · 02-05-2002, 12:24 AM

Quick and dirty C program that does what you ask.

Code:

/* stripdir.c */
#include <stdio.h>

void removeDir( char * pNew, char *szOldStr )
{
   char szTempStr[256];
   char * pTmp = pNew;

   while ( --pTmp != szOldStr )
   {
      if ( *pTmp == '/' )
      {
         *pTmp = '\0';
         break;
      }
   }
   strcpy( szTempStr, szOldStr );
   strcat( szTempStr, pNew+3 );
   strcpy( szOldStr, szTempStr );
}

main(int argc, char * argv[] )
{
   char * pNew;
   char szOldStr[256];

   strncpy( szOldStr, argv[1], 255 );

   while( ( pNew = (char *)strstr( szOldStr, "/../" ) ) != (char *) NULL )
   {
      removeDir( pNew, szOldStr );
   }
   printf("%s\n",szOldStr);
}

crabboy · 02-05-2002, 12:36 AM

Oops.. A directory like /home/../src/dude.c would seg fault my program. Here is a fix for that:

Code:

--- stripdir.c  Tue Feb  5 01:33:20 2002
+++ stripdir2.c Tue Feb  5 01:32:56 2002
@@ -5,7 +5,7 @@
    char szTempStr[256];
    char * pTmp = pNew;

-   while ( --pTmp != szOldStr )
+   while ( --pTmp )
    {
       if ( *pTmp == '/' )
       {

gluon · 02-05-2002, 01:51 AM

Hi Crabboy !

Wow ! Your code looks like... wow wow !!! I don't really understand it :-(

In fact, I have to thank you, because it works perfectly well ! I think that I'm going to use it, but in another project, which is completly written in C code.

In the mean time, I also found a bash-solution :

###################
function clean_path () {

local old=$1
local new=`echo $1 | sed -e 's/\/[^\/]*\/\.\.//'`
while [ $old != $new ]
do
old=$new
new=`echo $new | sed -e 's/\/[^\/]*\/\.\.//'`
done
echo $new
}
###################

As an example :

clean_path /users/ei3/gluon/Cours/Infographie/Mentor/../../Chapitres_Choisis/labo_02/../../../softwares/opera-5.0-static.i386/LICENSE

gives

/users/ei3/gluon/softwares/opera-5.0-static.i386/LICENSE

... and that's what I was looking for too...

Nevertheless, thank you for having spent time on my problem, and I hope that one day, I will be able to answer one of your questions ;-)

CU, Gluon