/*      CHAP_2_OUT_CONV.C                               */ 
 
/* This program uses the printf function to print the   */ 
/* various conversion specifications and their effect   */ 
/* on the output.                                       */ 
 
/* Include the proper header files in case printf has   */ 
/* to return EOF.                                       */ 
 
#include <stdlib.h> 
#include <stdio.h> 
#include <wchar.h> 
 
#define WIDE_STR_SIZE 20 
 
main() 
{ 
    double val = 123345.5; 
    char c = 'C'; 
    int i = -1500000000; 
    char *s = "thomasina"; 
    wchar_t wc; 
    wchar_t ws[WIDE_STR_SIZE]; 
 
    /* Produce a wide character and a wide character string */ 
 
    if (mbtowc(&wc, "W", 1) == -1) { 
        perror("mbtowc"); 
        exit(EXIT_FAILURE); 
    } 
 
    if (mbstowcs(ws, "THOMASINA", WIDE_STR_SIZE) == -1) { 
        perror("mbstowcs"); 
        exit(EXIT_FAILURE); 
    } 
 
    /* Print the specification code, a colon, two tabs, and the  */ 
    /* formatted output value delimited by the angle bracket     */ 
    /* characters (<>).                                          */ 
 
    printf("%%9.4f:\t\t<%9.4f>\n", val); 
    printf("%%9f:\t\t<%9f>\n", val); 
    printf("%%9.0f:\t\t<%9.0f>\n", val); 
    printf("%%-9.0f:\t\t<%-9.0f>\n\n", val); 
 
    printf("%%11.6e:\t\t<%11.6e>\n", val); 
    printf("%%11e:\t\t<%11e>\n", val); 
    printf("%%11.0e:\t\t<%11.0e>\n", val); 
    printf("%%-11.0e:\t\t<%-11.0e>\n\n", val); 
 
    printf("%%11g:\t\t<%11g>\n", val); 
    printf("%%9g:\t\t<%9g>\n\n", val); 
 
    printf("%%d:\t\t<%d>\n", c); 
    printf("%%c:\t\t<%c>\n", c); 
    printf("%%o:\t\t<%o>\n", c); 
    printf("%%x:\t\t<%x>\n\n", c); 
 
    printf("%%d:\t\t<%d>\n", i); 
    printf("%%u:\t\t<%u>\n", i); 
    printf("%%x:\t\t<%x>\n\n", i); 
 
    printf("%%s:\t\t<%s>\n", s); 
    printf("%%-9.6s:\t\t<%-9.6s>\n", s); 
    printf("%%-*.*s:\t\t<%-*.*s>\n", 9, 5, s); 
    printf("%%6.0s:\t\t<%6.0s>\n\n", s); 
    printf("%%C:\t\t<%C>\n", wc); 
    printf("%%S:\t\t<%S>\n", ws); 
    printf("%%-9.6S:\t\t<%-9.6S>\n", ws); 
    printf("%%-*.*S:\t\t<%-*.*S>\n", 9, 5, ws); 
    printf("%%6.0S:\t\t<%6.0S>\n\n", ws); 
} 

$ RUN  EXAMPLE
%9.4f:          <123345.5000>
%9f:            <123345.500000>
%9.0f:          <   123346>
%-9.0f:         <123346   >
%11.6e:         <1.233455e+05>
%11e:           <1.233455e+05>
%11.0e:         <      1e+05>
%-11.0e:        <1e+05      >
%11g:           <     123346>
%9g:            <   123346>
%d:             <67>
%c:             <C>
%o:             <103>
%x:             <43>
%d:             <-1500000000>
%u:             <2794967296>
%x:             <a697d100>
%s:             <thomasina>
%-9.6s:         <thomas   >
%-*.*s:         <thoma    >
%6.0s:          <      >
%C:             <W>
%S:             <THOMASINA>
%-9.6S:         <THOMAS   >
%-*.*S:         <THOMA    >
%6.0S:          <      >
$ 

/*      CHAP_2_STDIO.C  */ 
 
/* This program establishes a file pointer, writes lines from   */ 
/* a buffer to the file, moves the file pointer to the second   */ 
/* record, copies the record to the buffer, and then prints     */ 
/* the buffer to the screen.                                    */ 
 
#include <stdio.h> 
#include <stdlib.h> 
 
main() 
{ 
    char buffer[32]; 
    int i, 
        pos; 
    FILE *fptr; 
 
    /*  Set file pointer.            */ 
    fptr = fopen("data.dat", "w+"); 
    if (fptr == NULL) { 
        perror("fopen"); 
        exit(EXIT_FAILURE); 
    } 
 
    for (i = 1; i < 5; i++) { 
        if (i == 2)     /*  Get position of record 2. */ 
            pos = ftell(fptr); 
        /*  Print a line to the buffer.  */ 
        sprintf(buffer, "test data line %d\n", i); 
        /*  Print buffer to the record.  */ 
        fputs(buffer, fptr); 
    } 
 
    /*  Go to record number 2.       */ 
    if (fseek(fptr, pos, 0) < 0) { 
        perror("fseek");        /*  Exit on fseek error. */ 
        exit(EXIT_FAILURE); 
    } 
 
    /*  Read record 2 in the buffer. */ 
    if (fgets(buffer, 32, fptr) == NULL) { 
        perror("fgets");        /*  Exit on fgets error.  */ 
        exit(EXIT_FAILURE); 
    } 
    /*  Print the buffer.       */ 
    printf("Data in record 2 is: %s", buffer); 
    fclose(fptr);       /*  Close the file.     */ 
} 

$ RUN  EXAMPLE
Data in record 2 is: test data line 2

test data line 1 
test data line 2 
test data line 3 
test data line 4 

/*      CHAP_2_WC_IO.C                                          */ 
 
/* This program establishes a file pointer, writes lines from   */ 
/* a buffer to the file using wide-character codes, moves the   */ 
/* file pointer to the second record, copies the record to the  */ 
/* wide-character buffer, and then prints the buffer to the     */ 
/* screen.                                                      */ 
 
#include <stdio.h> 
#include <stdlib.h> 
#include <wchar.h> 
 
main() 
{ 
    char flat_buffer[32]; 
    wchar_t wide_buffer[32]; 
    wchar_t format[32]; 
    int i, 
        pos; 
    FILE *fptr; 
 
    /*  Set file pointer.            */ 
    fptr = fopen("data.dat", "w+"); 
    if (fptr == NULL) { 
        perror("fopen"); 
        exit(EXIT_FAILURE); 
    } 
 
    for (i = 1; i < 5; i++) { 
        if (i == 2)     /*  Get position of record 2. */ 
            pos = ftell(fptr); 
        /*  Print a line to the buffer.  */ 
        sprintf(flat_buffer, "test data line %d\n", i); 
        if (mbstowcs(wide_buffer, flat_buffer, 32) == -1) { 
            perror("mbstowcs"); 
            exit(EXIT_FAILURE); 
        } 
 
        /*  Print buffer to the record.  */ 
        fputws(wide_buffer, fptr); 
    } 
 
    /*  Go to record number 2. */ 
    if (fseek(fptr, pos, 0) < 0) { 
        perror("fseek");        /*  Exit on fseek error. */ 
        exit(EXIT_FAILURE); 
    } 
 
    /*  Put record 2 in the buffer.  */ 
    if (fgetws(wide_buffer, 32, fptr) == NULL) { 
        perror("fgetws");       /*  Exit on fgets error. */ 
        exit(EXIT_FAILURE); 
    } 
    /*  Print the buffer. */ 
    printf("Data in record 2 is: %S", wide_buffer); 
    fclose(fptr);               /*  Close the file.  */ 
} 

$ RUN  EXAMPLE
Data in record 2 is: test data line 2

test data line 1 
test data line 2 
test data line 3 
test data line 4 

/*      CHAP_2_FILE_DIS_AND_POINTER.C                           */ 
 
/* The following example creates a file with variable-length    */ 
/* records (rfm=var) and the carriage-return attribute (rat=cr).*/ 
/*                                                              */ 
/* The program uses creat to create and open the file, and      */ 
/* fdopen to associate the file descriptor with a file pointer. */ 
/* After using the fdopen function, the file must be referenced */ 
/* using the Standard I/O functions.                            */ 
 
#include <unixio.h> 
#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#define ERROR 0 
#define ERROR1 -1 
#define BUFFSIZE 132 
 
main() 
{ 
    char buffer[BUFFSIZE]; 
    int fildes; 
    FILE *fp; 
 
    if ((fildes = creat("data.dat", 0, "rat=cr", 
                        "rfm=var")) == ERROR1) { 
        perror("DATA.DAT: creat() failed\n"); 
        exit(EXIT_FAILURE); 
    } 
 
    if ((fp = fdopen(fildes, "w")) == NULL) { 
        perror("DATA.DAT: fdopen() failed\n"); 
        exit(EXIT_FAILURE); 
    } 
    while (fgets(buffer, BUFFSIZE, stdin) != NULL) 
        if (fwrite(buffer, strlen(buffer), 1, fp) == ERROR) { 
            perror("DATA.DAT: fwrite() failed\n"); 
            exit(EXIT_FAILURE); 
        } 
 
    if (fclose(fp) == EOF) { 
        perror("DATA.DAT: fclose() failed\n"); 
        exit(EXIT_FAILURE); 
    } 
}