strcspn
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                    | Defined in header  <string.h> | ||
| size_t strcspn( const char *dest, const char *src ); | ||
Returns the length of the maximum initial segment of the null-terminated byte string pointed to by dest, that consists of only the characters not found in the null-terminated byte string pointed to by src.
The behavior is undefined if either dest or src is not a pointer to a null-terminated byte string.
| Contents | 
[edit] Parameters
| dest | - | pointer to the null-terminated byte string to be analyzed | 
| src | - | pointer to the null-terminated byte string that contains the characters to search for | 
[edit] Return value
The length of the maximum initial segment that contains only characters not found in the null-terminated byte string pointed to by src
[edit] Notes
The function name stands for "complementary span" because the function searches for characters not found in src, that is the complement of src.
[edit] Example
Run this code
Output:
'abcde312$#@' contains invalid chars starting at position 8
[edit] References
- C11 standard (ISO/IEC 9899:2011):
- 7.24.5.3 The strcspn function (p: 368)
 
- C99 standard (ISO/IEC 9899:1999):
- 7.21.5.3 The strcspn function (p: 331)
 
- C89/C90 standard (ISO/IEC 9899:1990):
- 4.11.5.3 The strcspn function
 
[edit] See also
| returns the length of the maximum initial segment that consists of only the characters found in another byte string (function) | |
| (C95) | returns the length of the maximum initial segment that consists of only the wide chars not found in another wide string (function) | 
| finds the first location of any character in one string, in another string (function) | |
| C++ documentation for strcspn | |


