"Summarize" the common string-handling functions in C language

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There are no string types in the C language, but there are many string-handling functions available for the convenience of manipulating strings. such as:

input and output string, copy of string, connection, comparison and other operation functions. It is important to note that in the use of input and output, i.e. gets,

The puts function should introduce the header file <stdio.h>. When using other operation functions, the header file <string.h> is introduced. In addition, the use of connected

When you copy a string function, you must ensure that the remaining space of the target character array is sufficient to drop the new string and string Beam sign ' + '.

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The C language code is as follows:

/*** function: Copy the string from src to DST. The end of the string is also copied together. **SRC, or it can be a string constant. */char* my_strcpy (CHAR *DST, CONST CHAR *SRC) {     assert ( DST);      assert (SRC);          char  *ret = dst;         while  (*dst++ =  *src++)      {          ;      }     return  (ret);} /*** function: Connect the SRC string to the back of the string in DST, and delete the string flag "\" after DST. * * The return value of this function is the first address of DST. */char* my_strcat (CHAR *DST, CONST CHAR *SRC) {     assert ( DST);      assert (SRC);     char *ret = dst;           /*     ** looking for ' e ', the last of the DST      */     while  (*DST)      {           dst++;     }     /* Performing copy */      while  (*dst++ = *src++)      {           ;     }     return  (ret);} /* ** function: Compares the strings in two arrays in ASCII order and returns the comparison result by the return value of the function. * * String 1 = string 2, return value =0;** string 2〉 string 2, return value 〉0;** string 1〈 string 2, return value 〈0. */INT MY_STRCMP (CONST CHAR *DST, CONST CHAR *SRC) {      ASSERT (DST);      assert (SRC);          while  (*DST == *SRC)      {           if  (*dst ==  ')            {    &Nbsp;          return  (0);           }          dst++;           src++;     }      if  ((*DST - *SRC)  > 0)            return  (1);     else           return  (-1);} /*** function: The actual length of the string is measured (without the end of the string "\") and as a function return value. */int my_strlen (CONST CHAR *DST) {     assert (DST);          int ret = 0;          while  (*dst++)      {           ret++;     }     return  (ret);} /*** function: Determine if SRC is a sub-string of DST, and if so, returns the address of the first equal character, otherwise returns NULL. */       char* my_strstr (CHAR *DST, CHAR *SRC) {      assert (DST);      assert (SRC);           char *pdst = dst;     char *psrc  = src;     char *tmp = NULL;          if  (*src ==  ')            return  (DST);       /*     ** if the characters after the first are not equal,      **DST jumps to the position of the next character equal to the first time.      */     while  (*PDST)  &&  (*PSRC) )      {          tmp = pdst;                     while (*pdst == *psrc  &&  (*PSRC))            {                pdst++;                psrc++;          }           if  (*psrc ==  ')            {               return  ( TMP);          }           else          {                pdst = tmp;                psrc = src;                pdst++;           }     }     return  (NULL);}

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Dry tip: (void *) You can receive pointers of any type, but you must force type conversions if you want to use them at a time.

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"Summarize" the common string-handling functions in C language