Shell Programming and Scripting

$ mawk '$1=$1' RS= infile685
PC_1 wf_test1 Test
PC_2 wf_test2 Test
PC_3 wf_test3 Test

$ awk '$1=$1' RS= infile

PC_1
wf_test1
Test
PC_2 
wf_test2
Test
PC_3
wf_test3
Test

<PC_1

wf_test1
Test>
<PC_2 
wf_test2
Test>
<PC_3
wf_test3

Test>

colrot.c:

#include <stdio.h>
#include <string.h>

static char    buf[200000000];
static char    **bufs = NULL ;
static char    *cp, *cp2, *bcp ;
static char    *isep = "|\n" ;
static char    *osep = "\t" ;
static char    *bsep = "" ;
static int    rows = 1 ;
static int    cols ;
static int    col ;
static int    row ;
static int    bct = 0 ;

static int p_gets( char *b, size_t s )
{
    if ( !fgets( b, s, stdin ) )
    {
        if ( ferror( stdin ) )
        {
            perror( "stdin" );
            exit( 1 );
        }

        *b = NULL ;
        return 1 ;
    }

    return 0 ;
}

static void p_puts( char *b )
{
    if ( EOF == fputs( b, stdout ) )
    {
        if ( ferror( stdout ) )
        {
            perror( "stdout" );
            exit( 1 );
        }

        exit( 0 );
    }
}

main( int argc, char **argv )
{
    /* get $1 */
    for ( col = 1 ; col < argc ; col++ )
    {
        if ( !strcmp( argv[col], "-is" )
          && ++col < argc )
        {
            *isep = argv[col][0] ;
            continue ;
        }

        if ( !strcmp( argv[col], "-os" )
          && ++col < argc )
        {
            osep = argv[col] ;
            continue ;
        }

        if ( !strcmp( argv[col], "-bs" )
          && ++col < argc )
        {
            bsep = argv[col] ;
            continue ;
        }

        if ( ( rows = atoi( argv[col] ) ) > 0 )
        {
            continue ;
        }

        fputs(
"\n"
"Usage: colrot [ -is <i_sepc> ] [ -os <o_seps> ] [ -bs <b_seps> ] [ <lpb> ]\n"
"\n"
"Reads and saves a header line, and then reads <lpb> (default one) line\n"
"blocks, and writes the header and each block rotated, so each column is\n"
"on a line.  The character <i_sepc> (default pipe=|) defines input fields.\n"
"String <o_seps> (default a tab character) separates output fields.  A line\n"
"with string <b_seps> (default empty) separates output blocks.\n"
"\n"
            , stderr );
        exit( 1 );
    }

    /* get column name line */
    if ( p_gets( buf, sizeof( buf ) ) )
        exit( 0 );

    /* count columns */
    for ( cp = buf, cols = 0 ; *cp ; cols++ )
    {
        cp = strpbrk( cp, isep );
        cp++ ;
    }

    /* malloc a matrix of char pointers */
    if ( !( bufs = (char**)malloc( sizeof(char*) * cols * ( rows + 1 ))))
    {
        perror( "malloc()" );
        exit( 1 );
    }

    /* find and null terminate column names */
    for ( cp = buf, col = 0 ; col < cols ; col++ )
    {
        bufs[col] = cp ;
        cp = strpbrk( cp, isep );
        *cp = NULL ;
        cp++ ;
    }

    bcp = cp ;

    loop:

    /* read in N rows above header; rows + 1 total */
    for ( row = 1 ; row <= rows ; row++ )
    {
        /* ignore EOF until starting a new block */
        if ( p_gets( cp, sizeof(buf) - ( cp - buf ) ) )
        {
            if ( row == 1 ) /* nothing buffered */
            {
                exit( 0 );
            }
            /* shrink the last block and continue */
            /* we will read EOF again on row 1 of the next pass */
            rows = row - 1 ;
            break ;
        }

        /* locate and null terminate all columns, fake missing cols */
        for ( col = 0 ; col < cols ; col++ )
        {
            bufs[ col + ( row * cols ) ] = cp ;
            cp += strcspn( cp, isep );

            /* if sep found, null term field and step into next */
            switch ( *cp )
            {
            case 0:
                break ;
            case '\n':
                *cp = NULL ;
                break ;
            default:
                *cp = NULL ;
                cp++ ;
            }
        }

        /* write next line just past last field null */
        cp++ ;
    }

    /* go through matrix column and then reverse row,
        marking empty fields for supression */
    for ( col = 0 ; col < cols ; col++ )
    {
        for ( row = rows ; row > 0 ; row-- )
        {
            if ( *( bufs[ col + ( row * cols ) ] ) )
            {
                break ;
            }
    
            /* NULL pointer means nothing here or beyond */
            bufs[ col + ( row * cols ) ] = NULL ;
        }
    }

    if ( bct++ )
    {
        /* put a line between blocks */
        p_puts( bsep );
        p_puts( "\n" );
    }

    /* go through matrix column and then row, printing */
    for ( col = 0 ; col < cols ; col++ )
    {
        for ( row = 0 ; row <= rows ; row++ )
        {
            /* NULL pointer means nothing here or beyond */
            if ( !bufs[ col + ( row * cols ) ] )
            {
                break ;
            }

            if ( row )
            {
                p_puts( osep );
            }

            p_puts( bufs[ col + ( row * cols ) ] );
        }

        p_puts( "\n" );
    }

    /* start another block, reading just above header */
    cp = bcp ;
    goto loop ;
}