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QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
Utilities & Libraries
C Library Reference
R
re_comp()
Compile a regular expression

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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        Compile a regular expression
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        Compile a regular expression
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        Explain a regular expression error code
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        Retrieve an Open Control Block
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re_comp()

QNX SDP8.0C Library ReferenceAPIDeveloper

Compile a regular expression

Synopsis:

#include <unix.h>

char *re_comp( char *s );

Arguments:

s: A string that contains the regular expression that you want to compile. This string must end with a null byte and may include newline characters. If this argument is NULL, the current regular expression remains unchanged.

Library:

libregex

Use the -l regex option to qcc to link against this library.

Description:

The re_comp() function converts a regular expression string (RE) into an internal form suitable for pattern matching. Use this function with re_exec().

The re_comp() and re_exec() functions support simple regular expressions. The regular expressions of the form \{m\}, \{m,\}, or \{m,n\} aren't supported.

Note:

For better portability, use regcomp(), regerror(), and regexec() instead of these functions.

Returns:

NULL if the string pointed to by s was successfully converted. Otherwise, a pointer to one of the following error message strings is returned:

No previous regular expression
Regular expression too long
unmatched \(
missing ]
too many \(\) pairs
unmatched \)

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025