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strncpy(3) [osf1 man page]

strncat(3)						     Library Functions Manual							strncat(3)

NAME
strncat, strncmp, strncpy - Perform operations on string LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <string.h> char *strncat( char *s1, const char *s2, size_t n); int strncmp( const char *s1, const char *s2, size_t n); char *strncpy( char *s1, const char *s2, size_t n); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: strncat(), strncmp(), strncpy(): XSH4.2 Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
Points to a location containing the first string or array. Points to a location containing the second array. Specifies the number of bytes. In strncat(), n specifies the maximum number of bytes to append; in strncmp(), n specifies the maximum number of bytes to compare; and in strncpy(), n specifies the number of bytes to copy. DESCRIPTION
The strncat() function appends no more than n bytes from the array pointed to by the s2 parameter to the end of the array pointed to by the s1 parameter. The initial byte of the array pointed to by s2 overwrites the null byte at the end of a string pointed to by s1. It then appends a null byte to the result, and returns s1. When operating on overlapping objects, the behavior of this function is unreliable. The strncmp() function compares the string or array pointed to by the s1 parameter to the array pointed to by the s2 parameter. The sign of a nonzero value returned by strcmp() is determined by the sign of the difference between the values of the first pair of bytes (both interpreted as unsigned char) that differ in the two compared objects. The strncmp() functions compares bytes until it has compared n bytes or until it reaches a terminating null byte. The strncmp() function compares objects based on the machine collating order. It does not use the locale-dependent sorting order. Use the strcoll() or wcscoll() functions for locale-dependent sorting. The strncpy() function copies no more than n bytes from the array pointed to by the s2 parameter to the array pointed to by the s1 parame- ter. Bytes following a null byte are not copied. When operating on overlapping locations, the behavior of this function is unreliable. When the location pointed to by the s2 parameter is an array that is shorter than n bytes, null bytes are appended to the s1 value until n bytes in all are written. RETURN VALUES
Upon successful completion, the strncat() and strncpy() functions return a pointer to the resulting string or array. [Tru64 UNIX] Other- wise, these functions return a null pointer. Upon successful completion, the strncmp() function returns an integer whose value is greater than, equal to, or less than 0 (zero), accord- ing to whether the value of the s1 object is greater than, equal to, or less than the value of the s2 object. [Tru64 UNIX] When a success- ful comparison cannot be made, strncmp() returns a value of 0 (zero). RELATED INFORMATION
Functions: string(3), strcasecmp(3), strcat(3), strcmp(3), strcoll(3), strcpy(3), wcscoll(3), wcsncat(3), wcsncmp(3), wcsncpy(3) Standards: standards(5) delim off strncat(3)

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string(3)						     Library Functions Manual							 string(3)

NAME
strcat, strcmp, strcpy, strdup - Perform operations on strings LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <string.h> char *strcat( char *s1, const char *s2); int strcmp( const char *s1, const char *s2); char *strcpy( char *s1, const char *s2); char *strdup( const char *s1); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: strcat(), strcmp(), strcpy(): XSH4.2 strdup(): XSH4.2 Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
In strcat(), specifies the destination string for appending; in strcmp(), specifies the first of two strings to compare; in strcpy(), spec- ifies the destination string for the copying; and in strdup(), specifies the string to be duplicated. In strcat(), specifies the string to be appended to s1; in strcmp(), specifies the second of two strings to compare; and in strcpy(), specifies the source string for the copy- ing. Note [Tru64 UNIX] If you pass a NULL pointer as one of the const char * or char * parameters of a string manipulation function, the function generates a segmentation violation. To avoid the segmentation violation and cause the function to return zero, change the NULL pointer treatment for the process before issuing the call to the string manipulation function, as follows: Include the system header file sys/uswitch.h. Call the uswitch function, as described in the uswitch(2) reference page. The following program illustrates this procedure: #include <stdio.h> #include <sys/types.h> #include <sys/uswitch.h> main() { size_t retval; int uswitch_val; uswitch_val = uswitch(USC_GET,0); uswitch(USC_SET, uswitch_val | USW_NULLP); retval = strdup(NULL); DESCRIPTION
The strcat() function appends a copy of the string pointed to by the s2 parameter (including the terminating null byte) to the end of the string pointed to by the s1 parameter. The initial byte of s2 overwrites the null byte at the end of the string pointed to by s1. When operating on overlapping strings, the behavior of this function is unreliable. The strcmp() function compares the string pointed to by the s1 parameter to the string pointed to by the s2 parameter. The sign of a nonzero value returned by strcmp() is determined by the sign of the difference between the values of the first pair of bytes (both inter- preted as unsigned char) that differ in the two compared objects. The strcmp() function compares strings based on the machine collating order. It does not use the locale-dependent sorting order. Use the strcoll() or wcscoll() functions for locale-dependent sorting. The strcpy() function copies the string pointed to by the s2 parameter (including the terminating null byte) to the location pointed to by the s1 parameter. When operating on overlapping strings, the behavior of this function is unreliable. The strdup() function returns a pointer to a new string that is an exact duplicate of the string pointed to by the s1 parameter. The mal- loc() function is used to allocate space for the new string. RETURN VALUES
On successful completion, the strcat(), strcpy(), and strdup() functions return a pointer to the resulting string. Otherwise, these func- tions return a null pointer. The strdup() function sets errno to indicate the error. On successful completion, the strcmp() function returns an integer whose value is greater than, equal to, or less than 0 (zero), according to whether the s1 string is greater than, equal to, or less than the s2 string. ERRORS
If the strdup() function fails, errno may be set to the following value: Insufficient storage space is available. RELATED INFORMATION
Functions: malloc(3), memccpy(3), setlocale(3), strchr(3), strcoll(3), strlen(3), strncasecmp(3), strncat(3), strncmp(3), strncpy(3), strp- brk(3), strspn(3), strtok(3), strstr(3), strxfrm(3), swab(3), uswitch(2), wcscat(3), wcscmp(3), wcscpy(3) Standards: standards(5) delim off string(3)
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