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c庫源碼

發布時間: 2022-01-15 05:37:18

A. 如何查看c語言,內庫的源代碼

一般情況下是不能打開的。
除非使用反匯編軟體。但是反匯編軟體效果不盡如人意,需要人工猜測的地方太多!
而且如果使用了先進的代碼模糊技術的話,基本上很難看透源代碼的用意。
正常情況下,建議問作者索要源代碼,如果作者的軟體是閉源軟體的話,如果不是大神並且時間不多,那麼「打開exe格式的c語言文件的源代碼」
基本上就是天方夜譚了。

B. C語言庫函數源代碼

http://www.gnu.org/software/libc/這里就有所有的c標准庫函數源碼

C. 如何看c語言標准庫函數的源代碼

1、首先標准只是規定了這些函數的介面和具體的運行效率的要求,這些函數具體是怎麼寫得要看各個編譯器的實現和平台。

2、例如使用的編譯器是visual studio,微軟提供了一部分C運行時(CRT)的源碼,裡面會有memcpy,strcpy之類的函數的實現,在visual studio 2005下的路徑是C:Program FilesMicrosoft Visual Studio 8VCcrtsrc。

D. 在哪裡可以找到C語言標准庫的實現源代碼

linux下的glic庫的源碼鏈接:
http://ftp.gnu.org/gnu/glibc/,你可以下載最新版本的glibc-2.24.tar.gz這個壓縮文件,在Windows系統下直接用WinRAR解壓即可,如果在Linux系統下用命令行解壓的話,命令如下:tar -xzvf glibc-2.24.tar.gz。

E. c庫函數源碼

不是你表達不清,也許只是你根本不想仔細看一睛VC下面目錄的源碼,事實上就是有的。後附其中的qsort.c,以證明所言不虛。

VC的庫是提供源碼的,這東西也不值錢。
X:\Program Files\Microsoft Visual Studio\VCXX\CRT\SRC
注意有些可能本身是用匯編寫的。

/***
*qsort.c - quicksort algorithm; qsort() library function for sorting arrays
*
* Copyright (c) 1985-1997, Microsoft Corporation. All rights reserved.
*
*Purpose:
* To implement the qsort() routine for sorting arrays.
*
*******************************************************************************/

#include <cruntime.h>
#include <stdlib.h>
#include <search.h>

/* prototypes for local routines */
static void __cdecl shortsort(char *lo, char *hi, unsigned width,
int (__cdecl *comp)(const void *, const void *));
static void __cdecl swap(char *p, char *q, unsigned int width);

/* this parameter defines the cutoff between using quick sort and
insertion sort for arrays; arrays with lengths shorter or equal to the
below value use insertion sort */

#define CUTOFF 8 /* testing shows that this is good value */

/***
*qsort(base, num, wid, comp) - quicksort function for sorting arrays
*
*Purpose:
* quicksort the array of elements
* side effects: sorts in place
*
*Entry:
* char *base = pointer to base of array
* unsigned num = number of elements in the array
* unsigned width = width in bytes of each array element
* int (*comp)() = pointer to function returning analog of strcmp for
* strings, but supplied by user for comparing the array elements.
* it accepts 2 pointers to elements and returns neg if 1<2, 0 if
* 1=2, pos if 1>2.
*
*Exit:
* returns void
*
*Exceptions:
*
*******************************************************************************/

/* sort the array between lo and hi (inclusive) */

void __cdecl qsort (
void *base,
unsigned num,
unsigned width,
int (__cdecl *comp)(const void *, const void *)
)
{
char *lo, *hi; /* ends of sub-array currently sorting */
char *mid; /* points to middle of subarray */
char *loguy, *higuy; /* traveling pointers for partition step */
unsigned size; /* size of the sub-array */
char *lostk[30], *histk[30];
int stkptr; /* stack for saving sub-array to be processed */

/* Note: the number of stack entries required is no more than
1 + log2(size), so 30 is sufficient for any array */

if (num < 2 || width == 0)
return; /* nothing to do */

stkptr = 0; /* initialize stack */

lo = base;
hi = (char *)base + width * (num-1); /* initialize limits */

/* this entry point is for pseudo-recursion calling: setting
lo and hi and jumping to here is like recursion, but stkptr is
prserved, locals aren't, so we preserve stuff on the stack */
recurse:

size = (hi - lo) / width + 1; /* number of el's to sort */

/* below a certain size, it is faster to use a O(n^2) sorting method */
if (size <= CUTOFF) {
shortsort(lo, hi, width, comp);
}
else {
/* First we pick a partititioning element. The efficiency of the
algorithm demands that we find one that is approximately the
median of the values, but also that we select one fast. Using
the first one proces bad performace if the array is already
sorted, so we use the middle one, which would require a very
wierdly arranged array for worst case performance. Testing shows
that a median-of-three algorithm does not, in general, increase
performance. */

mid = lo + (size / 2) * width; /* find middle element */
swap(mid, lo, width); /* swap it to beginning of array */

/* We now wish to partition the array into three pieces, one
consisiting of elements <= partition element, one of elements
equal to the parition element, and one of element >= to it. This
is done below; comments indicate conditions established at every
step. */

loguy = lo;
higuy = hi + width;

/* Note that higuy decreases and loguy increases on every iteration,
so loop must terminate. */
for (;;) {
/* lo <= loguy < hi, lo < higuy <= hi + 1,
A[i] <= A[lo] for lo <= i <= loguy,
A[i] >= A[lo] for higuy <= i <= hi */

do {
loguy += width;
} while (loguy <= hi && comp(loguy, lo) <= 0);

/* lo < loguy <= hi+1, A[i] <= A[lo] for lo <= i < loguy,
either loguy > hi or A[loguy] > A[lo] */

do {
higuy -= width;
} while (higuy > lo && comp(higuy, lo) >= 0);

/* lo-1 <= higuy <= hi, A[i] >= A[lo] for higuy < i <= hi,
either higuy <= lo or A[higuy] < A[lo] */

if (higuy < loguy)
break;

/* if loguy > hi or higuy <= lo, then we would have exited, so
A[loguy] > A[lo], A[higuy] < A[lo],
loguy < hi, highy > lo */

swap(loguy, higuy, width);

/* A[loguy] < A[lo], A[higuy] > A[lo]; so condition at top
of loop is re-established */
}

/* A[i] >= A[lo] for higuy < i <= hi,
A[i] <= A[lo] for lo <= i < loguy,
higuy < loguy, lo <= higuy <= hi
implying:
A[i] >= A[lo] for loguy <= i <= hi,
A[i] <= A[lo] for lo <= i <= higuy,
A[i] = A[lo] for higuy < i < loguy */

swap(lo, higuy, width); /* put partition element in place */

/* OK, now we have the following:
A[i] >= A[higuy] for loguy <= i <= hi,
A[i] <= A[higuy] for lo <= i < higuy
A[i] = A[lo] for higuy <= i < loguy */

/* We've finished the partition, now we want to sort the subarrays
[lo, higuy-1] and [loguy, hi].
We do the smaller one first to minimize stack usage.
We only sort arrays of length 2 or more.*/

if ( higuy - 1 - lo >= hi - loguy ) {
if (lo + width < higuy) {
lostk[stkptr] = lo;
histk[stkptr] = higuy - width;
++stkptr;
} /* save big recursion for later */

if (loguy < hi) {
lo = loguy;
goto recurse; /* do small recursion */
}
}
else {
if (loguy < hi) {
lostk[stkptr] = loguy;
histk[stkptr] = hi;
++stkptr; /* save big recursion for later */
}

if (lo + width < higuy) {
hi = higuy - width;
goto recurse; /* do small recursion */
}
}
}

/* We have sorted the array, except for any pending sorts on the stack.
Check if there are any, and do them. */

--stkptr;
if (stkptr >= 0) {
lo = lostk[stkptr];
hi = histk[stkptr];
goto recurse; /* pop subarray from stack */
}
else
return; /* all subarrays done */
}

/***
*shortsort(hi, lo, width, comp) - insertion sort for sorting short arrays
*
*Purpose:
* sorts the sub-array of elements between lo and hi (inclusive)
* side effects: sorts in place
* assumes that lo < hi
*
*Entry:
* char *lo = pointer to low element to sort
* char *hi = pointer to high element to sort
* unsigned width = width in bytes of each array element
* int (*comp)() = pointer to function returning analog of strcmp for
* strings, but supplied by user for comparing the array elements.
* it accepts 2 pointers to elements and returns neg if 1<2, 0 if
* 1=2, pos if 1>2.
*
*Exit:
* returns void
*
*Exceptions:
*
*******************************************************************************/

static void __cdecl shortsort (
char *lo,
char *hi,
unsigned width,
int (__cdecl *comp)(const void *, const void *)
)
{
char *p, *max;

/* Note: in assertions below, i and j are alway inside original bound of
array to sort. */

while (hi > lo) {
/* A[i] <= A[j] for i <= j, j > hi */
max = lo;
for (p = lo+width; p <= hi; p += width) {
/* A[i] <= A[max] for lo <= i < p */
if (comp(p, max) > 0) {
max = p;
}
/* A[i] <= A[max] for lo <= i <= p */
}

/* A[i] <= A[max] for lo <= i <= hi */

swap(max, hi, width);

/* A[i] <= A[hi] for i <= hi, so A[i] <= A[j] for i <= j, j >= hi */

hi -= width;

/* A[i] <= A[j] for i <= j, j > hi, loop top condition established */
}
/* A[i] <= A[j] for i <= j, j > lo, which implies A[i] <= A[j] for i < j,
so array is sorted */
}

/***
*swap(a, b, width) - swap two elements
*
*Purpose:
* swaps the two array elements of size width
*
*Entry:
* char *a, *b = pointer to two elements to swap
* unsigned width = width in bytes of each array element
*
*Exit:
* returns void
*
*Exceptions:
*
*******************************************************************************/

static void __cdecl swap (
char *a,
char *b,
unsigned width
)
{
char tmp;

if ( a != b )
/* Do the swap one character at a time to avoid potential alignment
problems. */
while ( width-- ) {
tmp = *a;
*a++ = *b;
*b++ = tmp;
}
}

F. 求C語言中的庫函數的源代碼 如printf()函數,我要它的源代碼

在stdio.h中。如果是數學函數如sin()等的,在math.h中。而string類的函數則在string.h中。自己看吧

G. 完整的C++庫函數源代碼哪裡有下載

c庫函數源代碼
http://dsa7.fileflyer.com/d/427f1cec-63eb-4c6b-b7ac-da7c28595a8e/w44z/5SeIzB5/13898388clibsource.rar

H. linux下怎麼查看c函數庫的源代碼

頭文件在/usr/include/sys/time.h

如果要看定義,下載glibc的源代碼。

I. 誰能提供C語言stdio庫函數源代碼

http://mirrors.kernel.org/gnu/glibc/glibc-2.7.tar.gz
下載Linux的C語言標准庫,它包含stdio.h等等

J. c標准庫中的源碼實現細節需要看懂嗎

庫函數的實現細節源碼不需要完全看的東,作為一個程序員,首先需要掌握的是庫函數的功能、語法和用法。
至於庫函數的實現細節,可等有了基礎之後再去搞明白就可以了。搞明白哪些對自己的編程也是很有幫助的。

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