Substituting some characters in a text file (shell script).

grail · 07-01-2012, 10:47 AM

hmm ... usual story is that it might be nice to see a before and after of the data, how about:

Code:

awk 'ORS=length?" ":"\n"' infile > outfile

stf92 · 07-01-2012, 12:12 PM

I am beginning to see the complexities involved in the solution to this problem. So, and begging your pardon to all of you, dear LQers, I think I'll write a nice little program in C, language which, as this thread has shown me, is simpler than the bash script language. And yet,its manuals can fill libraries. My regards to all who have collaborated in this thread.

grail · 07-02-2012, 01:33 AM

Well as the OP it is of course always your choice on the direction you take, but I am curious as to what you have found
complex about any of the solutions? If none are meeting your requirements we are happy to see more examples to try and
assist

catkin · 07-02-2012, 03:35 AM

Quote:

Originally Posted by stf92

... I think I'll write a nice little program in C, language which, as this thread has shown me, is simpler than the bash script language. And yet,its manuals can fill libraries.

The C language itself is elegantly small and simple. It is the libraries developed for it that are huge and complex so need libraries of documentation.

stf92 · 07-02-2012, 04:53 AM

The truth is I want to have a program I understand and can therefore modify at will. In this respect, maybe some of you shall want to see this thread. Once again, I express my admiration for your labor in this forum.

stf92 · 07-04-2012, 01:30 AM

This is a possible solution to the problem. The program is self-documenting.

Code:








/* FILE NAME:  strip
 * PROG APPL:  postprocessor for when I post to LQ and write in the
 *   console.
 *
 * Compile with 'gcc -Wall -o strip strip.c'
 *
 * 
 * 1.  Removi la verificacion de EOF en la fputc y sigue andando (Restaurar).
 * 2.  
 *
 *
 * 
 *                    ANDANDO
 *
 *
 */

/*
 * Based on u2d.c, from Pacific.
 *
 */

#include        <stdio.h>
#include        <stdlib.h>

/*
 *      Unix To DOS text file conversion utility. 
 *
 *      Converts the Unix style end-of-line sequence 0AH
 *      to MS-DOS style end-of-line sequence 0DH 0AH
 */

#define TMPNAME "val"
#define LF 0x0a
#define CR 0x0d
#define BL 0x20

/*
 *      int     fixfile(char * filename)
 *
 *      "Fix" the text file specified by "filename".
 *      Returns 0 on error, non zero otherwise.
 */

int fixfile(char * filename) {
        FILE *          infile;
        FILE *          outfile;
        char            ch;
        unsigned long   in, out;

        printf("u2d: %s: ", filename);
        fflush(stdout);
        infile = fopen(filename, "r");  /* try to open input file */
        if (!infile) {
                printf("not found\n");
                return 0;
        }
        outfile = fopen(TMPNAME, "w");  /* try to open scratch file */
        if (!outfile) {
                fclose(infile);
                printf("unable to open temp file %s\n", TMPNAME);
                return 1;
        }
        in = out = 0;
        while ((ch = fgetc(infile)) != EOF) {   /* while not end of file */
        if (ch == 'LF') {
            /*******************/
            ch= fgetc(infile);
            if(ch == LF){
                fputc(LF, outfile);
                fputc(LF, outfile);
            } else {
                fputc(BL, outfile);
                fputc(ch, outfile);
            }        
                
        
            /*******************/
        }
        else {
            fputc(ch, outfile);
        }   
        }
        fclose(infile);
        fclose(outfile);
    
        printf("converted: %lu bytes read, %lu bytes written\n", in, out);
        return 0;
}

main(int argc, char ** argv)
{
        int     i;

        for (i = 1; i != argc; i++) {
                if (fixfile(argv[i])) {
                        printf("u2d: aborted!\n");
                        exit(1);
                }
        }
}
semoi@darkstar:~/script/el_mio/prog$ cat strip.c
/* FILE NAME:  strip   
 * PROG APPL:  postprocessor for when I post to LQ and write in the
 *   console.
 *
 * Compile with 'gcc -Wall -o strip strip.c'
 *
 * 
 * 1.  Removi la verificacion de EOF en la fputc y sigue andando (Restaurar).
 * 2.  
 *
 * WATCH OUT: there is a strip command already in the OS.
*
 * 
 *                    ANDANDO
 *
 *
 */

/*
 * Based on u2d.c, from Pacific.
 *
 */

#include        <stdio.h>
#include        <stdlib.h>

/*
 *      Unix To DOS text file conversion utility. 
 *
 *      Converts the Unix style end-of-line sequence 0AH
 *      to MS-DOS style end-of-line sequence 0DH 0AH
 */

#define TMPNAME "val"
#define LF 0x0a
#define CR 0x0d
#define BL 0x20

/*
 *      int     fixfile(char * filename)
 *
 *      "Fix" the text file specified by "filename".
 *      Returns 0 on error, non zero otherwise.
 */

int fixfile(char * filename) {
        FILE *          infile;
        FILE *          outfile;
        char            ch;
        unsigned long   in, out;

        printf("u2d: %s: ", filename);
        fflush(stdout);
        infile = fopen(filename, "r");  /* try to open input file */
        if (!infile) {
                printf("not found\n");
                return 0;
        }
        outfile = fopen(TMPNAME, "w");  /* try to open scratch file */
        if (!outfile) {
                fclose(infile);
                printf("unable to open temp file %s\n", TMPNAME);
                return 1;
        }
        in = out = 0;
        while ((ch = fgetc(infile)) != EOF) {   /* while not end of file */
        if (ch == LF) {
            ch= fgetc(infile);
            if(ch == LF){
                fputc(LF, outfile);
                fputc(LF, outfile);
            } else {
                fputc(BL, outfile);
                fputc(ch, outfile);
            }        
        }
        else {
            fputc(ch, outfile);
        }   
        }
        fclose(infile);
        fclose(outfile);
    
        printf("converted: %lu bytes read, %lu bytes written\n", in, out);
        return 0;
}

main(int argc, char ** argv)
{
        int     i;

        for (i = 1; i != argc; i++) {
                if (fixfile(argv[i])) {
                        printf("u2d: aborted!\n");
                        exit(1);
                }
        }
}
semoi@darkstar:~/script/el_mio/prog$