strchr

Defined in header `<string.h>`
char* strchr( const char* str, int ch );	(1)
/QChar/ strchr( /QChar/ str, int ch );	(2)	(since C23)

1) Finds the first 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 unsignedchar). The terminating null character is considered to be a part of the string and can be found when searching for '\0'.

2) Type-generic function equivalent to (1). Let T be an unqualified character object type.

If str is of type constT*, the return type is constchar*.
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 (strchr) 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 <stdio.h>
#include <string.h>

int main(void)
{
    const char *str = "Try not. Do, or do not. There is no try.";
    char target = 'T';
    const char* result = str;

    while((result = strchr(result, target)) != NULL)
    {
        printf("Found '%c' starting at '%s'\n", target, result);
        ++result; // Increment result, otherwise we'll find target at the same location
    }
}

Output:

Found 'T' starting at 'Try not. Do, or do not. There is no try.'
Found 'T' starting at 'There is no try.'

References

C23 standard (ISO/IEC 9899:2024):

7.24.5.2 The strchr function (p: TBD)

C17 standard (ISO/IEC 9899:2018):

7.24.5.2 The strchr function (p: TBD)

C11 standard (ISO/IEC 9899:2011):

7.24.5.2 The strchr function (p: 367-368)

C99 standard (ISO/IEC 9899:1999):

7.21.5.2 The strchr function (p: 330)

C89/C90 standard (ISO/IEC 9899:1990):

4.11.5.2 The strchr function

memchr	searches an array for the first occurrence of a character (function)
strrchr	finds the last occurrence of a character (function)
strpbrk	finds the first location of any character in one string, in another string (function)
C++ documentation for `strchr`

strchr

Parameters

Return value

Example

References

See also