xref: /freebsd/lib/libc/string/string.3 (revision d41afb814612ce005d93d2f8d127dcf6ea751cc4)

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.\"     @(#)string.3	8.2 (Berkeley) 12/11/93
.\"
.Dd September 2, 2023
.Dt STRING 3
.Os
.Sh NAME
.Nm stpcpy ,
.Nm strcat ,
.Nm strncat ,
.Nm strchr ,
.Nm strrchr ,
.Nm strcmp ,
.Nm strncmp ,
.Nm strcasecmp ,
.Nm strncasecmp ,
.Nm strcpy ,
.Nm strncpy ,
.Nm strerror ,
.Nm strlen ,
.Nm strpbrk ,
.Nm strsep ,
.Nm strspn ,
.Nm strcspn ,
.Nm strstr ,
.Nm strtok ,
.Nm index ,
.Nm rindex
.Nd string specific functions
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In string.h
.Ft char *
.Fn stpcpy "char *dst" "const char *src"
.Ft char *
.Fn strcat "char *s" "const char * append"
.Ft char *
.Fn strncat "char *s" "const char *append" "size_t count"
.Ft char *
.Fn strchr "const char *s" "int c"
.Ft char *
.Fn strrchr "const char *s" "int c"
.Ft int
.Fn strcmp "const char *s1" "const char *s2"
.Ft int
.Fn strncmp "const char *s1" "const char *s2" "size_t count"
.Ft int
.Fn strcasecmp "const char *s1" "const char *s2"
.Ft int
.Fn strncasecmp "const char *s1" "const char *s2" "size_t count"
.Ft char *
.Fn strcpy "char *dst" "const char *src"
.Ft char *
.Fn strncpy "char *dst" "const char *src" "size_t count"
.Ft char *
.Fn strerror "int errno"
.Ft size_t
.Fn strlen "const char *s"
.Ft char *
.Fn strpbrk "const char *s" "const char *charset"
.Ft char *
.Fn strsep "char **stringp" "const char *delim"
.Ft size_t
.Fn strspn "const char *s" "const char *charset"
.Ft size_t
.Fn strcspn "const char *s" "const char *charset"
.Ft char *
.Fn strstr "const char *big" "const char *little"
.Ft char *
.Fn strtok "char *s" "const char *delim"
.Ft char *
.Fn index "const char *s" "int c"
.Ft char *
.Fn rindex "const char *s" "int c"
.Sh DESCRIPTION
The string
functions manipulate strings terminated by a
null byte.
.Pp
See the specific manual pages for more information.
For manipulating variable length generic objects as byte
strings (without the null byte check), see
.Xr bstring 3 .
.Pp
Except as noted in their specific manual pages,
the string functions do not test the destination
for size limitations.
.Sh SEE ALSO
.Xr bstring 3 ,
.Xr index 3 ,
.Xr rindex 3 ,
.Xr stpcpy 3 ,
.Xr strcasecmp 3 ,
.Xr strcat 3 ,
.Xr strchr 3 ,
.Xr strcmp 3 ,
.Xr strcpy 3 ,
.Xr strcspn 3 ,
.Xr strerror 3 ,
.Xr strlen 3 ,
.Xr strpbrk 3 ,
.Xr strrchr 3 ,
.Xr strsep 3 ,
.Xr strspn 3 ,
.Xr strstr 3 ,
.Xr strtok 3 ,
.Xr simd 7
.Sh STANDARDS
The
.Fn strcat ,
.Fn strncat ,
.Fn strchr ,
.Fn strrchr ,
.Fn strcmp ,
.Fn strncmp ,
.Fn strcpy ,
.Fn strncpy ,
.Fn strerror ,
.Fn strlen ,
.Fn strpbrk ,
.Fn strspn ,
.Fn strcspn ,
.Fn strstr ,
and
.Fn strtok
functions
conform to
.St -isoC .