Eco C compiler pdf

Table _of Contents

Getting Started . . .

l

Features _of EcO-C _{. . . . . . . . . . . . . . . . . . .} . 2

Facts, Suggestions and Programming _{Hints. . . . . . . . .} 3

Using the ECO-C C Compiler. . . 5

Compiling the Program. _{. . . . . . . . . . . . . . .} 5

Compiler Switches. _{. . . . . . . . . . . . . . . . .} 5

Assembling the Program _{. . . . . . . .} . . . 7

Linking the Program. _{. . . . . . . . . . . . . . . .} 7

Linking Your Own _Functions. . . . 8

Reading and _Writing Data _{Files. . . . . . . . . . . . . .} 9

Writing an ASCII _Text

File

_{. . . . . . . . . . . . .} 9

Reading _{an ASCII} Text _{File . . . . . . . . . . . . .} 10

what _to Do

if

You Run _{Out of Memory} . . . 12

Standard _{Library of} C Functions . . . 13

Assembly Language _{Functions . . . . . . . . . . . . . . .} 24

Assembler Language _{Function Interface . . . . . . . . . .} 25

Invoking a Function in Assembler Language. _{. . . . .} 26

Using INIT.ASM _{. . . . . . . . . . . . . . . . . . .} 27

Naming Conventions _{. . . . . . . . . . . . . . . . .} 28

Creating Libraries. . . 29

CP/M _{I/O Interface.} . . . 31

Error Messages. _{. . . . . . . . . . . . . . . . . . . . .} 33

Quick _Function Reference. _{. . . . . . . . . . . . . . . .} 39

Operator Precedence. _{. . . . . . . . . . . . . . . .} 40

Getting Started

M&kinq ,a workinq Cqry

The

_first

_thing you should do is make a working copy of the ECo-C C

Compiler disk.

_If

you use the CP/M PIP

utility,

the sequence

is

_{to place your} CP/M disk with PIP on

it

in drive A and

a blank, formatted disk in b. (We have used <CR> to

signify

pressing the RETURN _key.)

A>PIP <CR>

* (now place the ECO-C _{disk in} A)

B:_=A:*.* <CR> (

<----

and _{enter this line)}

(Use DV _{option for copyinh}

After

the copy

is

completed, place the

original

disk in a safe

place and use the copy from now on. You

_will

need _the

_following

files

when _compiling a _program:

CP. COM _Macro

Pre-processor

XC. COM C _Compiler

XM. COM _{Code Generator}

CE. COM _{Error Reports}

CODE. PS _{Overhead Files}

CODE. PA " "

ERR. PA " "

STDIO. h _{Standard Definitions}

* .REL _Library Routines _(All of them)

M80 .COM _{Microsoft's Macro Assembler}

L80 .COM _{" Linker}

In

_addition,

each _{compiled program}

_will

_generate (on

_its

own)

TOKEN.CWK _and PCODE.CWK _{as intermediate}

_files

_{during compilation.}

These _intermediate

_{files will}

be _{erased automatically as the}

compilation _progresses. You _probably

_will

want _{to place your}

editor

on the disk, too (e.g., the

_editor

on _your CP/M disk is named ED.COM).

_If

_{you use} a _screen

editor

like

Micropro's

Wordstar, be _{sure you write your programs in} the "non-document" mode.

_Finally,

do _{not write programs using the}

file

names above.

If

disk space is a problem, the

_files

_{may have} a maximum

split

as follows: DISKI

-

CP.COM,ERR. PA XC.COM, XM.COM, CE.COM, CODE.PS, CODE.PA,

DISK2 _- M80.COM

DISK3 _- L80.COM, CFF.REL, CIF.REL, CFC.REL, CIC.REL, ECC.REL,

EC2. REL

Using the above

_distribution

_of

_files,

DISK2 may be used _for

the source

_file,

compiler output and _{assembler output.} DISKI

_is

used _for the _compiler and the _{compiler working}

_files;

_while DISK3

is used _{for linking} the _{output of} the assembler and the _compiler

libraries.

Depending _{on disk size, groupings of the} above _disks

may be done. For example, on a North _Star system DISK2 and DISK3

typically

would be combined _{into one disk (e.g.,} a DISK2) _.

Having made a working _copy of the Eco-C compiler, _{you are}

ready _{to write} and compile a C

program.

Features _of Eco—C

Before you

start

using the compiler, you should know what _is and _is not supported _{in this release.}

The

_full

C

syntax is supported _except; a.

bitfields

b.initializers(lnitializers

should be

_available

_in

April,

1983. Aggregate

_Initializers

are supported.) c. parametized macros

d. _{#line macro preprocessor directive}

e. in compound expression following a

#if

_{, macro}

ex-pansion _is not done

Most of the above

_will

be _{available in} subsequent _releases of _the

compiler. We _{also expect additional optimization} (we've

concen-trated

on longs and

floats

so

far)

to

substantially

shrink code

Facts, Suggestions and programming _Hints

The

_{following is}

a

list

of

specifications

and suggestions

that may _prove useful. Some represent "C spec" rules that are jÁQt

obeyed by

_existing

_compilers and _{might cause} an _{error message}

that would not be generated by _{other compilers.} Others are

limi-tations that

_will

disappear _shortly.

l.

unsigned long, unsigned char and _{unsigned short} data

types

_will

generate an _{error message.}

2. _{stdin, stdout, stderr} and

_stdlst

equate _to fdO,

_fdl,

_fd2, and fd3 _{respectively.} (A

file

named INIT.ASM _controls the number

of fcb's and _{lob's that are} generated _{plus setting} the _stack.) 3. On _function

_calls:

a. A _{function parameter of}

_float

_{is automatically}

pro-moted _to double and _{short or} char _{goes to an}

_int.

b. A

_function

_cannot

return

a char; only _an

int,

_- -'

unsigned, long, double, or pointer no matter how declareá. ' ' c. Given the choice of char or

int,

make

it

an

int.

It

avoids _{internal conversions,} thus improving speed.

4

. To

initialize

a pointer (e. g. , x_ ptr ) to a function

(e.g.,

_funcl())

, the syntax must be: x_ptr = &funcl;

5. A

_structure

_{or union name can only have two things done}

with

_it:

l)

take

_its

address with the address operator in

_front

of

_it,

or 2) have a period and a member _name

following

its

_name.

6. _{Binding of structure} members _to a _structure is absolute.

If

a pointer

is

to a

structure

sI and now you want to _use

it

with

S2, _you must _cast the _{pointer to} S2 _{or we}

_will

_{generate an}

error

message.

7.

_If

a

function

is not recursive, _{you are usually}

_better

off

to declare variables as

static

rather than auto or register.

If

generates _more

_efficient

code.

8. When _using a large "switch" _statement, place the most

likely

case Last and the least

_likely

_first.

9. _Currently we do support nested comments.

10. _#include's may be nested only two deep.

II.

Floating point numbers _can have _{up to} 17

_significant

digits.

The range

_for

_{the exponent is -38 to} +38. _{At the present}

time, only binary arithmetic is supported (BCD _{is forthcoming).}

12. _{Floating point} and _{long constants are} combined _{at run} time _rather than compile _{time. This, too,}

_will

be _fixed.

13.

_All

_{program source}

_f

_lies must _{terminate with} a

carriage-return, linefeed pair (CR-LF). _{Failure to} observe _this

_will

_cause the _{error handler to} produce odd _results.

:, ,

."? a. t " "

14. We _{do not yet have: lseek() ·QL-.c.un.link(> functions, and}

appending to a

f lle.

This

will

disappear when random

files

_are

finished.

The

_majority

_{of the}

_limitations

_mentioned above

_will

dis-appear _very soon. The _error handler

treats

all

_errors as

fatal;

there is no "cascading" of false error messages. When _you do _get an _{error, you}

will

find that

it

does diagnose the _error

correct-ly. Finally,

the

_library

is a

bit

_meager at present, but

will

grow shortly.

we _{think you}

_will

_find the Eco-C _{compiler more "UNIX-like"} than most on the market. Further,

it

perf _orms

its

_error checking

in

_strict

compliance _with the _{syntax defined} by K&R. _Finally, we

have adhered _to the _{function definitions} presented _in K&R _{as much} as possible in a CP/M environment.

Using _the ECO-C C _Compiler

writinq

^

Sollrce proqram

The

_first

_{step is to}

_write

the C

program using a

text

edi-tor.

(CP/M _{provides an}

_editor

_{stored on disk} as ED.COM.) Be _sure

that

you do not use the document mode on some

editors

(e.g.,

Wordstar). The document mode _{can turn the high}

_bit

ON _{and produce}

mysterious results on occasion.

Typically,

the

_file

extention given to a CP/M C _source

program

is

".C" (e.g., TEST.C). This is ñQt a requirement,

how-ever. You may _{use any}

file

extention _you wish.

cxmpÍl in.q

j=

proqram

Assuming the _compiler and the _{source pr"gram} (e.g., TEST.C)

is on drive A, the compiler is envoked by:

A>CP TEST <CR>

_/*

_Assumes a ".C" extention

*/

The _program

_will

_{supply the extention of} ".C"

_if

_{one is not}

supplied when _{the preprocessor}

_is

envoked.

_If

_{you supply} a

file

extention (e.g., ".XXX") _,

_it

_{overrides the}

_default

_(".C"). A

different

souce disk may be _specified. For example,

A>CP _B:TEST <CR>

The _program

_will

_{automatically}

_load and _{run the next two} passes of the compiler (XC and XM)

if

no _errors are detected. The

output of the

_final

pass

(i.e.,

XM) is an assembly language

source

file

(e.g., TEST.MAC). This can be examined and modified

if

you wish.

Compiler Switches

- i

This switch

tells

the compiler to use the integer

version of the

_printf

() _function.

It

avoids _{pulling in} the

float-ing _point

_library

whenever

_printf

() _{is used.}

If

your program does not _use

_floating

_point numbers,

_this

_option

_will

produce _smaller code _size.

As an _{example, suppose} a _{source program} is named TEST.C. To

use

it

with

this

option, the compiler would be _{invoked with the}

following command

_line

_arguments:

A>cp _test

_-i

causing the TEST _{program to use the integer version of}

_printf

_().

Note _that lower _case

_letters

may be used

if

_you wish.

-c This switch uses the

library

where getchar() and

putchar() do

_direct

BDOS

_calls

_{to CP/M}

_{for input/output}

_(I/O)

rather than through getc() and _{putc(). This avoids console I/O} from going _through the

_{f lle}

_handlers thus _{generating smaller} code

size.

_It

is envoked _with the _following command

_line

_arguments:

A>cp _{test -c}

-o This switch is used to change _{the name of the output}

file

and the _drive on which

it

is written. For example:

A>cp _{test -o} b:

_test

A>cp _{test -ob:}

_test

Both _{of the} above examples _{are allowed.}

_If

a

file

type is added

to the

_{f lle}

name the default type of '.MAC'

will

not be used.

-b This switch is used _{to turn}

_off

most _{of the} messages and

_statistics

the _{compiler generates.}

NOTE:

_All

or part of the switches may be used when compiling

a _program. Each switch option in the command

line

must be

sepa-rated one from the other by a blank _space; the order is

unimpor-tant. Example:

A>cp _test

_-i

_-c or

A,qsemb1 _{inq Hie proqram}

The assembler _output

_file

from the _compiler (e.g., TEST.MAC)

becomes _{the input}

_file

_{to the assembler.} Your package _includes

Microsoft's Macro 80 _assembler.

It

is envoked _with the _following

command _:

A>M80 =TEST

_/*

_{Note blank space}

_*/

Since M80 _{has a}

default f lle

extention of .MAC, _{the assembler may} be used _{with or without} the .MAC _extention.

The _output

_{f lle}

_{from the assembler}

_will

be named TEST.REL.

Further

_details

about using M80

are in the Microsoft manual. NOTE: _there must be a blank _space between M80 and the equal sign

(=) when _the assembler _is envoked _for CP/M.

.Idlin.kinq :

=

Proqram

· ": [" {', U" " _,

The .REL

_file

_{from the assembler is then linked to the}

standard

_library

routines (e.g., -CF.RELb EC2.REL, _etc.) by _using

the Microsoft linker (L80). A _{typical link would be:}

A>L80 TEST,TEST/N/E

which causes TEST.REL to be the _input

_file

and produces an _output

f

_lle

named TEST.COM. TEST.COM _{becomes the executable} C

program.

The _standard

_library

_{routines are automatically} searched.

If

you wanted the input

file

TEST.REL _to have a command

f lle

name _of PRICE.COM, _{the syntax would be:}

A>L80 TEST,PRICE/N/E

Linking in Your Own _Functions

Suppose _{that you} have compiled and assembled a function _you

wrote with the name DATE.C. The assembler would have generated a REL

_{f lle}

_named DATE.REL. Now _{you want to}

_link

_{the function into} a

program named TEST.C. _{The command arguments would be:}

A>L80 TEST,DATE,TEST/n/e

^ ^ ^

l l I

input .REL

_file----

I

---

output .COM

file

I

.REL _{function(s) to} be _{linked with program}

The

_{first file}

name

following

180 on the command

line is

the

input

_{f lle}

(.REL). The

_{last f lle}

_{name (before the}

_{"/n/e") is}

_the

output (.COM) _program

_file.

_In between _{these two}

_file

_{names are} the (.REL) _{function(s) you} want _to

_link

_{in with} the _program. Each must be _{separated from the other} by a _comma.

Again, _{additional details} on L80 are found in the Microsoft

manual.

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Reading and _Writing Data

_{f lies}

We _{have attempted to} make

_file

_input and _output

_(i.e.,

I/O)

as consistent

with

the UNIX operating system as possible given the _differences between

_it

and CP/!¢l. _{Below is an example of}

writ-ing to and _{then reading from} a

file

using the ECO-C compiler.

Both programs in source are included on your

distribution

disk.

/*

Writing an ASCII Data File

*/

#include "stdio.h"

_/*

Include

_file

overhead _info

_*/

#define CLEARS 12

_/*

_{Clear screen for} ADDS _Viewpoint

_*/

#define MAX ₁₀₀₀

_/*

_{Maximum number of characters}

_*/

main()

{

int

_i;

char _c; FILE _*fp;

putchar (CLEARS) _;

_/*

_{Clear the screen}

_*/

if

((fp = fopen("TEXT.TXT", "W")) == NULL) {

puts("Can't open TEXT.TXT") ;

exit(-l);

l*

Signals an Error

*/

}

puts("Enter line of text and press RETURN:

_\n")

_;

for

_(i

= O; (c = getchar()) !=

'\n'

&&

_i

< _{MAX; ++i)}

putc(c,

_fp);

putc (CPMEOF, _{fp) ;}

l*

Must _write

_{end-of-file */}

fclose(fp);

}

The program begins _with the _{#include preprocessor directive}

to include the

_file

I/O information needed _{to work with disk}

files.

The _{#defines are} used _to def _ine the _{clear screen} code _for an ADDS _{Viewpoint and set the maximum number of characters that}

can be entered.

The _{main() function} marks _{the beginning of the program} and

several variables _{are declared.} The FILE _{typedef refers to the}

structure that is

defined in stdio.h and

_is

used _{to establish}

pointers to

_fp

and _{fopen(). Generally,}

_high-level

_file

_I/O

_will

require the

_file

_{declarations to} be _{present in every} program that

works _{with disk}

_files.

The

_call

_to putchar(CLEARS) _{simply clears} the _{screen in preparation for entering} the _text.

If

your terminal requires two or more characters to clear the screen, change _{the #define to} be a

string

and change the

putchar(CLEARS) _{statement to} a puts(). For example,

if

_{you are}

using a SOROC terminal which _uses an _escape (033 octal) followed

by an asterisk (*), the #define would be: #define CLEARS "\033*". You _{would then use puts(CLEARS) instead of putchar(CLEARS) since} we _are now treating CLEARS as a string.

The

_if

_{statement attempts to open} a

text f lle

using the _name

TEXT.TXT _{in the} ASCII

_"write"

mode.

_If

_the

_file

_cannot be opened

(i.e.,

fp returns a NULL), a _message is displayed that the

file

cannot be opened and _{the program is aborted} by _the

_call

_to

exit().

The

_-l

_{argument in the}

_{exit() function call is}

used _to

signal that some _error occurred.

If all

went

_well,

_{fp serves} as our

link with

the

file

that was

just

opened (e.g., TEXT.TXT). A _{prompt asks the user to enter} a

line

of text, pressing RETURN when _they have _{finished. Calls to}

getchar () _{take the characters}

_f

_{rom the keyboard and assign them}

to c. A check

is

made to see

if

the character was a newline

(

i.

e. , a

'\n'

which corresponds to pressing RETURN) or

i

f

i

exceeds the maximum number _{of characters allowed} (MAX).

If

the _{tests are} passed, a

call

_{to putc() places character} c

into the _{buffer associated with fp.} The

_for

_{loop continues}

_until

MAX

-

l

characters or RETURN is entered. When that happens, a

final call

is made _{to putc() using the} CP/M

_end-of-file

_{(OxIA) as}

the character. This is necessary when _{using the} ASCII mode

_for

disk

_files.

A

_call

_{to fclose()}

_writes

_{the buffer to the disk} and _closes the

_{f lle}

and the _program ends.

Readjnq _{Añ ASCII. Texk} Fj1e

The _{program to} read _the

_text

_file

_just

_created

_closely

follows the _program used _{to write} the

_{f lle.}

_{Notice that} main() _is

called

_with

two arguments: argc and _argv. The _argc

_{variable is}

used _{to count the} number _of command

_line

_{arguments (argument}

counter) used when the _{program was} envoked. The _{argvll variable}

is an _{array of pointers} that points to what command

line

argu-ments _were entered.

For _{example, to} read _the TEXT.TXT

_file,

_this

_{program is} envoked _with:

A>READFILE _TEXT.TXT<CR>

/*

Reading an ASCII data

f lle */

#include "stdio.h"

/*

Pull in the overhead _info again

_*/

#define CLEARS 12

l*

Clear _{screen for} ADDS viewpoint */

main(argc, argv)

int

argc;

char *argv1l;

{

char _c; FILE _*fp;

putchar (CLEARS) _;

if

(argc != 2) {

printf ("I

need _to know the

_file

name.\n\n") ;

printf

("Use: \n\nA>READFILE FILENAME.XXX") ;

exit (-l)

; }

if

((fp

= fopen(argv1ll,

"r"))

== NULL) {

printf

("Can't open

file:

%s",

argvlll);

exit(-l);

}

while( (c = getc (fp)) != EOF)

putchar(c);

fclose(fp);

}

There _{are two arguments (argc} = 2) and two pointers in

argvlj

(argvlOl pointing to READFILE and

_argvlll

_{pointing to} TEXT.TXT). _{In the program, the argc}

_is

checked _to make _{sure that} two arguments were supplied when the program was envoked.

If

argc

is

not equal to 2, _{an error} message is given and the program

aborts.

If

the argument count is

_correct,

we

try

to _open the

file

in

the ASCII _"read" mode.

_If

the

_{f lle}

_{pointer (fp) returned} from the

call

to fopen()

_is

a NULL, _{an error message} is given and the

program aborts.

If

a

valid

file

pointer is returned, while

while

loop does

repeated _{calls to getc()} and assigns the _{character in} the _buffer

to c. The

_call

_{to putchar()} displays the characters on the CRT.

This continues

_until

the _end-of-f

_lle

(EOF) _{is sensed, whereupon}

the

_file

_{is closed} and the _program ends.

It

may be a worthwhile excercise to

list

stdio.h _{to see} how

the various symbolic constants _{are def ined (e.g.,} FILE, NULL,

EOF,

_etc.),

_{although you probably}

will

not need _to know _the

details contained therein.

what _to Do

if

You Run _{Out of M=ory}

Unlike many other C

compilers that are available, the ECO-C

compiler does _{not require that the}

_entire

_source code _{of the} program to reside in memory. Even _so,

_it

_{is possible to} "run _out

of memory". _Usually,

_{this is}

caused by _{overflowing the} symbol

table space.

Space _for the symbol _{table is allocated dynamically.} As _auto

variables _{are compiled, they are treated} as temporaries and

"discarded" af ter the function has been _{compiled. Very long}

programs

with

a _large number _{of global} variables

(i.e.,

_extern

storage class) or a _{very large} function with _{many auto-type}

variables are the most

_likely

_{to cause} the symbol _{table to}

over-flow.

If

this

happens,

_all

_{is not}

_lost.

_{Simply break the source}

program

into

two separate source programs and then compile and

link

them _together.

For example, _{suppose your source program} TEST.C _{runs out of}

memory during a compile. Further _assume that _you inspect TEST.C

and

_find

_{that the program can be}

_split

_in

_{half after}

a function

definition

named _root().

Using your

editor,

create a _new

file

called TESTI.C;

this

will

be a _new

file.

Now read in TEST.C and delete

all

of the

lines

from the beginning of the program to the

start

of the

definition

of

_root().

TESTI.C _{should now contain the "second}

half"

of TEST.C. Save TESTI.C on disk. Now load TEST.C and delete

everything from the

_definition

_of the _root()

_f

_{unction to} the end of the _program and save

_it

on disk.

Having done _the above, TEST.C _{contains the}

_"first

_half"

_of the _{original program} and TESTI.C _contains the "second _half ". Now

compile and assemble _{the two separately} and _then

_link

them

to-gether to form _{one program. The sequence might look}

_like:

A>cp TEST

A>cp TESTI

A>m80 =TEST

A>m80 =TEST1

A>l80 TEST,TEST1,TEST/n/e

which creates an executable _program named TEST.COM with both

Standard _{Library of} C _Functions

Listed _{below are the functions} that comprise the Eco-C

Standard Function

_Library.

Each _function

_is

_{described by name}

with any argument

_list

_{that might} be necessary for the

f

unction

call.

_If

the function returns a data type other than integer

(i.e., int),

the data type returned preceeds the

_function

name. The _{functions are arranged in alphabetical order}

_for

_easier

reference.

alloc ()

char _*alloc(u)

_l*

Request _{for storage}

_*/

unsigned _u;

Returns a pointer to u bytes of storage, where each byte is able

to store one char.

If

the request

for

u bytes of storage cannot

be

_satisfied,

_{the pointer returned equals} NULL

_(i.e.,

_zero).

Therefore, a _{non-zero pointer} value returned from the

call

to

alloc() means that u bytes of consecutive storage _are available.

atol ()

atol (S)

_l*

Return _integer of _string

_*/

char _*s;

Returns the integer value of the

_string

pointed to by _{"*s". This}

f

unction permits the _{input string to} be _{in decimal,} hex _{or octal}

using the standard C

syntax

_for

such _{values (e.g., "Oxff").}

atol()

long atol(s)

_l*

Return long of _string

_*/

char _*s;

Functions in the same _manner as atoi() _, except the _{returned value}

is a long rather than _an

_int.

ca1loc()

cha r *calloc(count, size)

_/*

Request _storage *

_/

unsigned _{count, size;}

Returns a pointer _to

sufficient

_{storage to for} "count" _items,

each _of which _{requires "size" bytes} of _storage.

_If

the _{request is}

successful, each _{byte is}

_initialized

_to NULL.

If

the request for storage cannot be

_satisfied,

_{the pointer returned equals} NULL

(i.e.,

zero). The _{pointer returned, therefore, can} be _{tested to} see

if

the request was

satisf

led.

dec imaí ()

long decimal(s)

_l*

Return _{long of} decimal

_*/

char _*s;

Returns the _{long value} of a decimal string pointed to by "*s".

exit

()

int exit(i)

l*

terminate a _program

*/

int

_i;

Used _{to terminate} a _program. A _non-zero value for

"i"

is normally

used _{to indicate that} some _error occurred when this

f

unction was

called.

free ()

int

free(c)

_l*

Release _{storage area}

_*/

char _*c;

The _function

_call

_frees (i.e., tie-allocates) the _region of stor-age pointed to by "c", thus making that area of storage available

for

re-use. The function assumes

that

the pointer "c" was

first

ftoa()

int

ftoa(s, d, _{prec, type)}

_/*

_{Float to} ASCII

_*/

char *s ;

double d;

int

prec, type;

Converts a

_floating

point number "d"

_into

_{an ASCII}

string

and

stores the

_result

in "s". Up _to 18

_{significant digits}

_of

preci-sion may be requested

(i.e.,

_prec = 18). The "type"

variable

_may

be

_'g',

_{'e' or}

_'f'

Isee _{discussion of the}

_printf

()

_function];

otherwise the

_floating

point number _{is free-form. Since the}

string is null

terminated

_{(i.e., '\0'),}

"s" must be _large enough

to hold "prec" bytes +

l

characters.

fclo8e()

int

fclose (fp)

_l*

close a

file

*/

FILE _*fp;

Function

_first

_calls

Eflush() to flush the contents of the

buffer

and _{then closes the}

_file

_{associated with the "fp"}

_file

pointer. This frees "fp" for use with another

file if

desired.

fflush()

int

fflush(fp)

/*

write buffer to disk

*/

FILE

_*f

_p;

Writes the _{current contents} of the _{buffer associate with "fp" to} the _{disk (including} the EOF _indicator)

.

fgets()

cha r *fgets (s,

_i,

_lop)

_/*

_{get string from}

file

*/

char *s ;

i

nt

_i

;

FILE _*iop;

Reads

_"i"

_{characters from lop and places them into the character}

array "s". The

f

unction terminates upon reading:

(l)

a

_null

character

_('\0'),

( _{2) and}

end-of-file

indicator,

or (3)

i-l

characters. The _{character string at} "s" _{is null terminated ('\0')} upon return. The _{function returns} a pointer _{to the}

_string,

_or

zero

if

end-of-f

_lle

or an _error occurred.

_fi1lbuff

()

int

_{_}

_fillbuff

(fp)

_/*

read _{buffer of} data

_*/

FILE _*fp;

Used _{to replentish} the _{buffer associated with fp} and _{returns the} next _character or EOF.

fopen()

FILE _*f open (name, mode)

_l*

open

file

*/

cha r *name, *mode;

Open _the

_file

"name"

_for

_{use in the} "mode"

_file

_operation. There are two possible modes of operation:

"r " Open _{for reading. The}

file

must _{already exist to use}

this

mode. ASCII

_text

_files

have

_{thecarriage-return,}

line-f

eed

_(i.

_{e. ,} <CR><LF>) _adjustment.

"rb" Open _{for binary reading.} No _{<cr><lf> adjustments.}

"w" Open _for

_writing.

_{Any existing}

_file

_{with the} same

"name" _is destroyed and a new

file

is created. The

contents of the _old

_file

are

_lost.

Does <CR><LF>

adjustment.

"wb" Open _{for binary writing.} No _{<cr><lf> adjustments.}

Upon a successful _open, the

f

unction returns a pointer (e.g., fp)

fputs C)

int

fputs(s, lop)

_l*

Put a character out */

char _*s; FILE _*iop;

Takes _{the character pointed to} by _"s" and _puts

_it

_{to the output}

designated by _"lop".

getc()

int

getc (p)

_l*

Read _character from

_file

_*/

FILE _*p;

Reads a character from the input stream _{associated with} "p". The

character is normally returned as a positive integer although

it

may return EOF _{upon reading}

_end-of-file

_or TERR

if

an

_error

occurred during the read. _Rml. L.

·r

getchar ()

int

getchar()

_l*

Get _character from _stdin

_*/

Reads a single character from stdin.

stdin

defaults to the

tetmi nal.

gets ()

char _*gets(buff)

_/*

Get a string from _sdtin

_*/

char _*buff ;

Get a string from stdin and place

it

in the buffer pointed to by

"*buff".

_If

input

_is

from the console,

_'\r'

_is

used _{to sense the} ená _of the _input

_string;

otherwise a newline

'\n'

is used.

getw()

int

getw(fp)

_/*

Get next word from

_file

_*/

FILE _*fp;

Reads _{the next word, or integer, from the}

_file

_associated

_with

fp. The word _{is returned}

_if

a successful read is done, but _may

also return EOE' _{upon reading}

_end-of-file

_{or "ER·Rv,if an}

error

occurred during the read. PJL'LG

hex ()

long hex(s)

_l*

Return long from hexs

_*/

char _*s;

Convert the hex _{string pointed to} by _{"*s" into} a long data _type.

isalpha ()

int

isalpha(c)

_/*

Is c alphabeticcharacter

*/

char _c;

If

the character "c" is an alphabetic character, TRUE

(i.e., l)

is returned; otherwise FALSE _(i.e., O)

is returned.

isdigit()

int isdigit(i)

/*

Is

_i

a

digit */

int

i

;

If

the character

_{"i" is}

a

digit,

TRUE (I) is returned; otherwise

islower()

int

islower(c)

_l*

Is c lower _case

letter */

char _c;

If

the character "c" is a lower-case alphabetic character, TRUE

(l)

is returned; otherwise FALSE (O) _{is returned.}

isspace ()

int

isspace(c)

_l*

Is c white _space

*/

char _c;

If

the character "c" is a tab

('\t'),

a _space ('

'),

a newline

('\n')

or a

carriage return

('\r'),

TRUE

(l)

i

s

returned;

otherwise FALSE (O) _{is returned.}

isupper ()

int

isupper (C)

_/*

_{Is c in upper case}

_*/

char _c;

If

the charactez "c"

_is

an _upper-case

letter,

TRUE

(l)

i

s

returned: otherwise FALSE (O) _{is returned.}

octa1()

long _octal(s)

_/*

Return long _{of octal}

_{str */}

char _*s;

Returns _long of the _{octal string pointed to} by _"*s",

printf

()

;"',

i::" ;'; iii i" '!".?:'í.:fl'!i. t'":_t!. ;?

Tj'jÉ'"q |'"ll": ;""r'-:'t'f"" t"' i'"' " """"Éf'l'!"·'·"l'"f'l"'"" ' :'" "'_i"/"i i " i";j]

" "! 'i ií'l 'i 'i' U t"'; j"í ' ' "' 'i' " t" l-,, , t ' ,!, S . . i , ,.. 't t : :::1' :_{::.:: ·:.} 1" l'": '.:.' l5'..!!s,i'.".,'!

i é l"' ,::.i'?.·.í'..l!?l'..'!f!... .$.

,.. ... , .,.t.; :i. !"' .f. '.-.·.''..: 'i. !' : '.. i ! '.-..' ',.."'..! l ! ".'..l ' {..f .:, t..; $ ?... . ,., ,,.t. t..' !

·- A minas ii:ign bel ore the conversion control character

j.r!dicaceb t:

hat the _{output is to} be

_{left-justifieCL}

print£("%--d", x) ;

'Ñiii j-et"t-j: mLit'y the ccmtents _{of variable "x".}

nn A

_digit

:_"íU"it'.g

consisting of "nn"

_diqíts

_following the ccmverz' Ñu) cxaractez' and preceeding the _control

ch:'i '"_a

"' k ' _{¿f't i}

ifií"s

the minimum

field

width to be used

For E'j iiu:

i

[!{:íg

if

padding _{is required}

_(i.e.

_, numt: _{-er is} i:_maUeu: t-§";{3.ütrle _{width) blanks areusedunlessthe}

"it

'_i: f'íÑ-'it _iS a _zero which _causes paddina with zeros.

.y J

printf("%i2d", x);

p:" .Z ."!_t: ' _úf; c..n-,zábie "x" in _a

f

ield of 12 _positions.

It

í'7.3 _y z j :_-,> lu-± úsí'id _{with a decimal point:}

printf

("%6.2f", x);

whiic.i': _'.u'iítt"s .in _a

_field

_{width of} 6 _{places and}

reserves

L-2"¡//g :_-;,,g.;;j$

after the decin'.al _point.

t

';jjg; :

-jt--':i ',-üdth _spL"cifi€r may also be used with s-:

tring

·: i U?_{t.-' -.}

printf('k25,'"",

_str);

wf.ic:_{t' rg}

_i:

_:ts the _fix-st 25 _{characters of the strinq} \T?1F.iaLjZt:

"si"r"

_{(right.-jus'tified).}

i _{¿jt: at.t,,3} :_,n:.-tí íúi. daía _ít:em _is a long rather than an

int.

(Thini

l

-' Ue

letter 'i!",

not _a oneÁ

tjíii,'""t

_f"jj.'j",

X);

-The ':_(jR'lgrLí"i c"i". _{zractet'z" ava"'i}

o The data item is printed in octal notation (unsigned) _. x The data item is printed in hexadecimal notation

(un-signed) _·" q¿ L t"l'£: !' '"

u The data item is printed in unsigned decimal notation. c The data item is printed _as a single character.

s Thedata item is a

string.

The itemmustbenull term-inated or have a width specification equal to _or less

than the _length of the _string.

e The data item is a

float

_or double and is printed in

scientific

notation. Default precision is 6

_digits,

but may be modified with an "nn" specifier.

f

The áata item _is a

float

_or double and is printed in

decimal _{notation with} a default precision of 6

digits.

The _precision may be changed with an "nn" specifier* g Select the shorter of options e _or

f

(i.eg, _use the

one with the shortest width) .

The _{conversion characters way be in upper or lower case}

_letters

(they are converted to lower case during the parse of the control

string) .

putc()

int

putc(c, p)

_/*

Output a character */

cha r c ;

struct iobbuf *p;

Outputs the character "c" to the stream pointed to by _"p" and

returns the _character "C"b

putchar ()

int

putchar(c)

_/*

Send _{character to stdout}

_*/

cliar c;

Outputs the character "c" to stdout which is normally _the con-sole. (Thia

_{function calls}

putc() with "c" and _{stdout as}

_its

arguments.)

putw ( )

int

putw(u, _fp)

_/*

_Output a word

*/

unsigned _u; FILE

_*f

p;

Outputs the unsigned _integer word "u" _to the stream _{pointed to} by

"fp". This

_function

is accomplished by

_calls

_{to putc() with the}

lower byte sent

_first

_followed by the _{high byte.} "Word" _is taken

to be two bytes _{in length.}

strcat ()

int strcat(s,

t)

_l*

Concatenate _{strings */}

char _*s,

_*t;

The

_string

_{pointed to} by

_{"t" is}

_concatenated

_(i.e.,

added) _onto

the end _{of the}

_string

_{pointed to} by _"s".

_It

_{is the programmer's}

responsibility to ensure that the character _{array pointed to} by

"s"

_is

large enough _{to hold both "s"} and _the appended

_string

_at

"t" (including the NULL _terminator

_'\0').

strcmp()

int

strcnip(s, t)

_/*

Compare _{strings */}

char _*s,

_*t;

Compares _{the two}

_sttings

"s" and

_"t"

_{character-by-character.}

_If

the two

_strings

match, a value of zero

is

returned. Otherwise,

the _{function returns the result} of the _subtraction of the

charac-ter

in

_"t"

from the character in "s". For _example,

_if

_the match

fails

on the

fifth

character and SI41 = 'A' and t14j = 'B',

-l

is

returned

_(i.e.,

'A' _in ASCII = 65, 'B' in ASCII = 66; therefore,

-I

= 65 _{- 66).}

If

follows

that a negative value is returneá

if

the liSCII value in

_"t"

is greater than the ASCII _{value in "s".}

Positive values are returned when the ASCII value in

"t"

is less

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Assembly Language _Functions

The _{following is} a

list

of assembly language functions that

may be used. The are part of the EC2.REL _disk

_file.

They _should be _{self-explanatory.}

double _atof(s)

_/*

Convert ASCII _to

_{float */}

char _*s;

i

nt bdos(val,call)

_/*

CPM BDOS

_{call */}

int val,call;

int

,_ftoa(s,db)

_/*

Convert double _to ASCII

_*/

char _*s; double db;

_

exit

()

/*

Close

files

and end program

*/

int

open(s)

_/*

Open

_{f lle}

named _str

_*/

char _*s;

int

creat(s)

_l*

Create a

file

namt"d _str

_"/

char _*s;

int c:

lose(fd)

_/*

Cícwe

_tile

_{associated with} Ed _*/'

int

write(fd,buf,n)

_/*

Write tc device */' char _*buf;

/*

_if

_file

i/o

then n must be mult:

iple

of 128 */

'

r

/*

Read device

*/

ítít

read(fd,buf, .) '

char _*buf;

I*

same note as write

*/

chain(s)

_l*

Load and ruri a _program chain("fileaame") *1

ci"iar _*s;

char _*sbrk(u)

_/*

Return u- bytes of storage

*/

Assembler Language _{Function Interface}

Assembly language _routines ínay be written and called by the

"C" _{program or other assEInbler language functions.} There

_exist

several support routines that may be used _{to simplify} assembler

language _interface.

$RTN

-

will

return the value pointed to by the HL register pair to the _calling

_f

_unction.

$RETVAL

-

will

return the value contained iri the DE register pair to the

_calling

_function.

_If

a long was requested then the value

_will

be padded.

$RETM1

-

will

return a -1 to the calling program.

$FE _{·- calK: the function pointed to by the} HL

register pair using parameters _following the

_call

and _{information contained in} the

called function.

$PPAR!Q

- pushes the parameter addressed in DE for the _{length in} BC.

when a

function

is defined, the

fiu't

word in the

function

following the _function name is the amount of stack _{space required}

far

'working storage Ly _the

_function.

_This

_is

_{expres3ed as} a

^

negative value. This stack space is the equivalent to auto variables. The code

_for

_the

_function

_immediately

_{follows this}

word. For example:

FAKE: _: DEFY _-8

LD _IX

,O

etc ©

LD HI, ,ANSWER

JP $RTN##

states that 8 _bytes OZ _working

stack storage are required by the

function

FAKE. The _stack

_will

_always

_contain

8 _{bytes of}

administrative data _{prior to} the requested _storage.