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Diffstat (limited to 'man/man3/strcat.3')
| -rw-r--r-- | man/man3/strcat.3 | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/man/man3/strcat.3 b/man/man3/strcat.3 new file mode 100644 index 00000000..fe717fbc --- /dev/null +++ b/man/man3/strcat.3 @@ -0,0 +1,268 @@ +.TH STRCAT 3 +.SH NAME +strcat, strncat, strcmp, strncmp, cistrcmp, cistrncmp, strcpy, strncpy, strecpy, strlen, strchr, strrchr, strpbrk, strspn, strcspn, strtok, strdup, strstr, cistrstr \- string operations +.SH SYNOPSIS +.B #include <u.h> +.br +.B #include <libc.h> +.PP +.ta \w'\fLchar* \fP'u +.B +char* strcat(char *s1, char *s2) +.PP +.B +char* strncat(char *s1, char *s2, long n) +.PP +.B +int strcmp(char *s1, char *s2) +.PP +.B +int strncmp(char *s1, char *s2, long n) +.PP +.B +int cistrcmp(char *s1, char *s2) +.PP +.B +int cistrncmp(char *s1, char *s2, long n) +.PP +.B +char* strcpy(char *s1, char *s2) +.PP +.B +char* strecpy(char *s1, char *es1, char *s2) +.PP +.B +char* strncpy(char *s1, char *s2, long n) +.PP +.B +long strlen(char *s) +.PP +.B +char* strchr(char *s, char c) +.PP +.B +char* strrchr(char *s, char c) +.PP +.B +char* strpbrk(char *s1, char *s2) +.PP +.B +long strspn(char *s1, char *s2) +.PP +.B +long strcspn(char *s1, char *s2) +.PP +.B +char* strtok(char *s1, char *s2) +.PP +.B +char* strdup(char *s) +.PP +.B +char* strstr(char *s1, char *s2) +.PP +.B +char* cistrstr(char *s1, char *s2) +.SH DESCRIPTION +The arguments +.I s1, s2 +and +.I s +point to null-terminated strings. +The functions +.IR strcat , +.IR strncat , +.IR strcpy , +.IR strecpy , +and +.I strncpy +all alter +.IR s1 . +.I Strcat +and +.I strcpy +do not check for overflow of +the array pointed to by +.IR s1 . +.PP +.I Strcat +appends a copy of string +.I s2 +to the end of string +.IR s1 . +.I Strncat +appends at most +.I n +bytes. +Each returns a pointer to the null-terminated result. +.PP +.I Strcmp +compares its arguments and returns an integer +less than, equal to, or greater than 0, +according as +.I s1 +is lexicographically less than, equal to, or +greater than +.IR s2 . +.I Strncmp +makes the same comparison but examines at most +.I n +bytes. +.I Cistrcmp +and +.I cistrncmp +ignore ASCII case distinctions when comparing strings. +The comparisons are made with unsigned bytes. +.PP +.I Strcpy +copies string +.I s2 +to +.IR s1 , +stopping after the null byte has been copied. +.I Strncpy +copies exactly +.I n +bytes, +truncating +.I s2 +or adding +null bytes to +.I s1 +if necessary. +The result will not be null-terminated if the length +of +.I s2 +is +.I n +or more. +Each function returns +.IR s1 . +.PP +.I Strecpy +copies bytes until a null byte has been copied, but writes no bytes beyond +.IR es1 . +If any bytes are copied, +.I s1 +is terminated by a null byte, and a pointer to that byte is returned. +Otherwise, the original +.I s1 +is returned. +.PP +.I Strlen +returns the number of bytes in +.IR s , +not including the terminating null byte. +.PP +.I Strchr +.RI ( strrchr ) +returns a pointer to the first (last) +occurrence of byte +.I c +in string +.IR s , +or +.L 0 +if +.I c +does not occur in the string. +The null byte terminating a string is considered to +be part of the string. +.PP +.I Strpbrk +returns a pointer to the first occurrence in string +.I s1 +of any byte from string +.IR s2 , +.L 0 +if no byte from +.I s2 +exists in +.IR s1 . +.PP +.I Strspn +.RI ( strcspn ) +returns the length of the initial segment of string +.I s1 +which consists entirely of bytes from (not from) string +.IR s2 . +.PP +.I Strtok +considers the string +.I s1 +to consist of a sequence of zero or more text tokens separated +by spans of one or more bytes from the separator string +.IR s2 . +The first call, with pointer +.I s1 +specified, returns a pointer to the first byte of the first +token, and will have written a +null byte into +.I s1 +immediately following the returned token. +The function +keeps track of its position in the string +between separate calls; subsequent calls, +signified by +.I s1 +being +.LR 0 , +will work through the string +.I s1 +immediately following that token. +The separator string +.I s2 +may be different from call to call. +When no token remains in +.IR s1 , +.L 0 +is returned. +.PP +.I Strdup +returns a pointer to a distinct copy of the null-terminated string +.I s +in space obtained from +.IR malloc (2) +or +.L 0 +if no space can be obtained. +.PP +.I Strstr +returns a pointer to the first occurrence of +.I s2 +as a substring of +.IR s1 , +or 0 if there is none. +If +.I s2 +is the null string, +.I strstr +returns +.IR s1 . +.I Cistrstr +operates analogously, but ignores ASCII case differences when comparing strings. +.SH SOURCE +All these routines have portable C implementations in +.BR /sys/src/libc/port . +Many also have machine-dependent assembly language +implementations in +.BR /sys/src/libc/$objtype . +.SH SEE ALSO +.IR memory (2), +.IR rune (2), +.IR runestrcat (2) +.SH BUGS +These routines know nothing about +.SM UTF. +Use the routines in +.IR rune (2) +as appropriate. +Note, however, that the definition of +.SM UTF +guarantees that +.I strcmp +compares +.SM UTF +strings correctly. +.PP +The outcome of overlapping moves varies among implementations. |