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Homework and Emergencies Homework & Coursework Questions ls in specific columns
# 15  
Old 11-09-2011
Quote:
Originally Posted by agama
Or a very small tweek to the original code I posted:

Code:
ls -pt | awk '
    /\/$/ {
        dcol[didx++] = $0;
        if( length( $0 ) > dmax )
            dmax = length( $0 );
        next;
    }
    {
        ccol[cidx++] = $0;
        next;
    }
    END {
        fmt = sprintf( "%%-%ds %%s\n", dmax );
        stop = didx > cidx ? didx : cidx;
        for( i = 0; i < stop; i++ )
            printf( fmt, dcol[i], ccol[i] );
    }
'

If you're needing this from a compiled programme, I'd do the work in the programme.
Wow, that code was impressive...
It's exactly what i wanted !
The code that i use with .txts has a little problems with columns...it's not lined up.. Smilie
But this is perfect i think ...!
I don't know maybe it's a little too "specialized" for my project but thanks it's really educational..
Only a question, if i need to run this command inside a C programm under UNIX shell i should use the system(); and put inside the parenthesis the command??
Anyway thanks!Smilie
# 16  
Old 11-09-2011
Quote:
Originally Posted by giampoul
Only a question, if i need to run this command inside a C programm under UNIX shell i should use the system(); and put inside the parenthesis the command??
I'd put it in a script and invoke the script using system(), much cleaner than trying to force the script into a C string.

Code:
#!/usr/bin/env ksh
awk '
.... awk programme goes here
' 
exit $?

If your file is named list_cols.ksh and is in a directory that is in the PATH, then your system() call should just be:
Code:
system( "list_cols.ksh" );

---------- Post updated at 21:34 ---------- Previous update was at 21:07 ----------

It's messy, and I'd have to think hard about approving it during a code walk through, but you could put it in a system() call directly if you don't want to maintain the additional script:

Code:
system(
        "ls -pt | awk '"
            "/\\/$/ {"
                "dcol[didx++] = $0;"
                "if( length( $0 ) > dmax )"
                    "dmax = length( $0 );"
                "next;"
            "}"
            "{"
                "ccol[cidx++] = $0;"
                        "next;"
            "}"
            "END {"
                "fmt = sprintf( \"%%-%ds %%s\\n\", dmax );"
                "stop = didx > cidx ? didx : cidx;"
                "for( i = 0; i < stop; i++ )"
                    "printf( fmt, dcol[i], ccol[i] );"
            "}'");

Last edited by agama; 11-09-2011 at 10:20 PM.. Reason: a wee bit more info
This User Gave Thanks to agama For This Post:
giampoul
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