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10.3 Regular Expression Matching

The GNU C Library supports two interfaces for matching regular expressions. One is the standard POSIX.2 interface, and the other is what the GNU C Library has had for many years.

Both interfaces are declared in the header file regex.h. If you define _POSIX_C_SOURCE, then only the POSIX.2 functions, structures, and constants are declared.

• POSIX Regular Expression Compilation
• Flags for POSIX Regular Expressions
• Matching a Compiled POSIX Regular Expression
• Match Results with Subexpressions
• Complications in Subexpression Matching
• POSIX Regexp Matching Cleanup