strrchr

Defined in header <string.h> 
char *strrchr( const char *str, int ch );
 (1) 
/*QChar*/ *strrchr( /*QChar*/ *str, int ch );
 (2) (since C23)
1) Finds the last occurrence of ch (after conversion to char as if by (char)ch) in the null-terminated byte string pointed to by str (each character interpreted as unsigned char). The terminating null character is considered to be a part of the string and can be found if searching for '\0'.
2) Type-generic function equivalent to (1). Let T be an unqualified character object type.
  • If str is of type const T*, the return type is const char*.
  • Otherwise, if str is of type T*, the return type is char*.
  • Otherwise, the behavior is undefined.
If a macro definition of each of these generic functions is suppressed to access an actual function (e.g. if (strrchr) or a function pointer is used), the actual function declaration (1) becomes visible.

The behavior is undefined if str is not a pointer to a null-terminated byte string.

Parameters

str - pointer to the null-terminated byte string to be analyzed
ch - character to search for

Return value

Pointer to the found character in str, or null pointer if no such character is found.

Example

#include <string.h>
#include <stdio.h>
 
int main(void)
{
    char szSomeFileName[] = "foo/bar/foobar.txt";
    char *pLastSlash = strrchr(szSomeFileName, '/');
    char *pszBaseName = pLastSlash ? pLastSlash + 1 : szSomeFileName;
    printf("Base Name: %s", pszBaseName);
}

Output:

Base Name: foobar.txt

References

  • C11 standard (ISO/IEC 9899:2011):
    • 7.24.5.5 The strrchr function (p: 368-369)
  • C99 standard (ISO/IEC 9899:1999):
    • 7.21.5.5 The strrchr function (p: 331)
  • C89/C90 standard (ISO/IEC 9899:1990):
    • 4.11.5.5 The strrchr function

See also

finds the first occurrence of a character
(function)
finds the first location of any character in one string, in another string
(function)
C++ documentation for strrchr

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