Character and string library functions
The
Informix® ESQL/C library
contains the following character-manipulation functions. You can use
these functions in your C programs to manipulate single characters
and strings of bytes and characters, including variable-length expressions
of the following data types:
- varchar
- fixed-size lvarchar
The internal structure referenced by the lvarchar pointer data type is different from the character representation of a fixed-size lvarchar variable. You must use the ifx_var() functions to manipulate lvarchar pointer variables. For more information about the ifx_var() functions, see The lvarchar pointer and var binary library functions.
The
functions whose names begin with by act on and return fixed-length
strings of bytes. The functions whose names begin with rst and st (except stchar)
operate on and return null-terminated strings. The rdownshift() and rupshift() functions
also operate on null-terminated strings but do not return values.
When you compile your Informix®
ESQL/C program
with the esql preprocessor, it calls on the linker
to link these functions to your program. The following list provides
brief descriptions of the character and string library functions and
refers you to the pages where detailed information for each function
is given.
| Function name | Description | See |
|---|---|---|
| bycmpr() | Compares two groups of contiguous bytes | The bycmpr() function |
| bycopy() | Copies bytes from one area to another | The bycopy() function |
| byfill() | Fills an area you specify with a character | The byfill() function |
| byleng() | Counts the number of bytes in a string | The byleng() function |
| ldchar() | Copies a fixed-length string to a null-terminated string | The ldchar() function |
| rdownshift() | Converts all letters to lowercase | The rdownshift() function |
| rstod() | Converts a string to a double value | The rstod() function |
| rstoi() | Converts a string to a short integer value | The rstoi() function |
| rstol() | Converts a string to a 4-byte integer value | The rstol() function |
| rupshift() | Converts all letters to uppercase | The rtypmsize() function |
| stcat() | Concatenates one string to another | The stcat() function |
| stchar() | Copies a null-terminated string to a fixed-length string | The stchar() function |
| stcmpr() | Compares two strings | The stcmpr() function |
| stcopy() | Copies one string to another string | The stcopy() function |
| stleng() | Counts the number of bytes in a string | The stleng() function |