1confstr(3C) Standard C Library Functions confstr(3C)
2
6 confstr - get configurable variables
7
9 #include <unistd.h>
10 size_t confstr(int name, char *buf, size_t len);
12
15 The confstr() function provides a method for applications to get con‐
16 figuration-defined string values. Its use and purpose are similar to
17 the sysconf(3C) function, but it is used where string values rather
18 than numeric values are returned.
19 The name argument represents the system variable to be queried.
22 If len is not 0, and if name has a configuration-defined value, conf‐
25 str() copies that value into the len-byte buffer pointed to by buf. If
26 the string to be returned is longer than len bytes, including the ter‐
27 minating null, then confstr() truncates the string to len−1 bytes and
28 null-terminates the result. The application can detect that the string
29 was truncated by comparing the value returned by confstr() with len.
30 If len is 0, confstr() still returns the integer value as defined
33 below, but does not return the string.
34 The confstr() function supports the following values for name, defined
37 in <unistd.h>, for both SPARC and x86:
38 _CS_LFS64_CFLAGS
40 If _LFS64_LARGEFILE is defined in <unistd.h>, this value is the set
42 of initial options to be given to the cc and c89 utilities to build
43 an application using the Large File Summit transitional compilation
44 environment (see lfcompile64(5)).
45 _CS_LFS64_LDFLAGS
48 If _LFS64_LARGEFILE is defined in <unistd.h>, this value is the set
50 of final options to be given to the cc and c89 utilities to build
51 an application using the Large File Summit transitional compilation
52 environment (see lfcompile64(5)).
53 _CS_LFS64_LIBS
56 If _LFS64_LARGEFILE is defined in <unistd.h>, this value is the set
58 of libraries to be given to the cc and c89 utilities to build an
59 application using the Large File Summit transitional compilation
60 environment (see lfcompile64(5)).
61 _CS_LFS64_LINTFLAGS
64 If _LFS64_LARGEFILE is defined in <unistd.h>, this value is the set
66 of options to be given to the lint utility to check application
67 source using the Large File Summit transitional compilation envi‐
68 ronment (see lfcompile64(5)).
69 _CS_LFS_CFLAGS
72 If _LFS_LARGEFILE is defined in <unistd.h>, this value is the set
74 of initial options to be given to the cc and c89 utilities to build
75 an application using the Large File Summit large file compilation
76 environment for 32-bit applications (see lfcompile(5)).
77 _CS_LFS_LDFLAGS
80 If _LFS_LARGEFILE is defined in <unistd.h>, this value is the set
82 of final options to be given to the cc and c89 utilities to build
83 an application using the Large File Summit large file compilation
84 environment for 32-bit applications (see lfcompile(5)).
85 _CS_LFS_LIBS
88 If _LFS_LARGEFILE is defined in <unistd.h>, this value is the set
90 of libraries to be given to the cc and c89 utilities to build an
91 application using the Large File Summit large file compilation
92 environment for 32-bit applications (see lfcompile(5)).
93 _CS_LFS_LINTFLAGS
96 If _LFS_LARGEFILE is defined in <unistd.h>, this value is the set
98 of options to be given to the lint utility to check application
99 source using the Large File Summit large file compilation environ‐
100 ment for 32-bit applications (see lfcompile(5)).
101 _CS_PATH
104 If the ISO POSIX.2 standard is supported, this is the value for the
106 PATH environment variable that finds all standard utilities. Oth‐
107 erwise the meaning of this value is unspecified.
108 _CS_POSIX_V6_ILP32_OFF32_CFLAGS
111 If sysconf(_SC_V6_ILP32_OFF32) returns -1, the meaning of this
113 value is unspecified. Otherwise, this value is the set of initial
114 options to be given to the c99 utility to build an application
115 using a programming model with 32-bit int, long, pointer, and off_t
116 types.
117 _CS_POSIX_V6_ILP32_OFF32_LDFLAGS
120 If sysconf(_SC_V6_ILP32_OFF32) returns -1, the meaning of this
122 value is unspecified. Otherwise, this value is the set of final
123 options to be given to the c99 utility to build an application
124 using a programming model with 32-bit int, long, pointer, and off_t
125 types.
126 _CS_POSIX_V6_ILP32_OFF32_LIBS
129 If sysconf(_SC_V6_ILP32_OFF32) returns -1, the meaning of this
131 value is unspecified. Otherwise, this value is the set of libraries
132 to be given to the c99 utility to build an application using a pro‐
133 gramming model with 32-bit int, long, pointer, and off_t types.
134 _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS
137 If sysconf(_SC_V6_ILP32_OFFBIG) returns -1, the meaning of this
139 value is unspecified. Otherwise, this value is the set of initial
140 options to be given to the c99 utility to build an application
141 using a programming model with 32-bit int, long, and pointer types,
142 and an off_t type using at least 64 bits.
143 _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS
146 If sysconf(_SC_V6_ILP32_OFFBIG) returns -1, the meaning of this
148 value is unspecified. Otherwise, this value is the set of final
149 options to be given to the c99 utility to build an application
150 using a programming model with 32-bit int, long, and pointer types,
151 and an off_t type using at least 64 bits.
152 _CS_POSIX_V6_ILP32_OFFBIG_LIBS
155 If sysconf(_SC_V6_ILP32_OFFBIG) returns -1, the meaning of this
157 value is unspecified. Otherwise, this value is the set of libraries
158 to be given to the c99 utility to build an application using a pro‐
159 gramming model with 32-bit int, long, and pointer types, and an
160 off_t type using at least 64 bits.
161 _CS_POSIX_V6_LP64_OFF64_CFLAGS
164 If sysconf(_SC_V6_LP64_OFF64) returns -1, the meaning of this value
166 is unspecified. Otherwise, this value is the set of initial options
167 to be given to the c99 utility to build an application using a pro‐
168 gramming model with 64-bit int, long, pointer, and off_t types.
169 _CS_POSIX_V6_LP64_OFF64_LDFLAGS
172 If sysconf(_SC_V6_LP64_OFF64) returns -1, the meaning of this value
174 is unspecified. Otherwise, this value is the set of final options
175 to be given to the c99 utility to build an application using a pro‐
176 gramming model with 64-bit int, long, pointer, and off_t types.
177 _CS_POSIX_V6_LP64_OFF64_LIBS
180 If sysconf(_SC_V6_LP64_OFF64) returns -1, the meaning of this value
182 is unspecified. Otherwise, this value is the set of libraries to be
183 given to the c99 utility to build an application using a program‐
184 ming model with 64-bit int, long, pointer, and off_t types.
185 _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS
188 If sysconf(_SC_V6_LPBIG_OFFBIG) returns -1, the meaning of this
190 value is unspecified. Otherwise, this value is the set of initial
191 options to be given to the c99 utility to build an application
192 using a programming model with an int type using at least 32 bits
193 and long, pointer, and off_t types using at least 64 bits.
194 _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS
197 If sysconf(_SC_V6_LPBIG_OFFBIG) returns -1, the meaning of this
199 value is unspecified. Otherwise, this value is the set of final
200 options to be given to the c99 utility to build an application
201 using a programming model with an int type using at least 32 bits
202 and long, pointer, and off_t types using at least 64 bits.
203 _CS_POSIX_V6_LPBIG_OFFBIG_LIBS
206 If sysconf(_SC_V6_LPBIG_OFFBIG) returns -1, the meaning of this
208 value is unspecified. Otherwise, this value is the set of libraries
209 to be given to the c99 utility to build an application using a pro‐
210 gramming model with an int type using at least 32 bits and long,
211 pointer, and off_t types using at least 64 bits.
212 _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS
215 This value is a <newline>-separated list of names of programming
217 environments supported by the implementation in which the widths
218 of the blksize_t, cc_t, mode_t, nfds_t, pid_t, ptrdiff_t, size_t,
219 speed_t, ssize_t, suseconds_t, tcflag_t, useconds_t, wchar_t, and
220 wint_t types are no greater than the width of type long.
221 _CS_XBS5_ILP32_OFF32_CFLAGS
224 If sysconf(_SC_XBS5_ILP32_OFF32) returns −1 the meaning of this
226 value is unspecified. Otherwise, this value is the set of initial
227 options to be given to the cc and c89 utilities to build an appli‐
228 cation using a programming model with 32-bit int, long, pointer,
229 and off_t types.
230 _CS_XBS5_ILP32_OFF32_LDFLAGS
233 If sysconf(_SC_XBS5_ILP32_OFF32) returns −1 the meaning of this
235 value is unspecified. Otherwise, this value is the set of final
236 options to be given to the cc and c89 utilities to build an appli‐
237 cation using a programming model with 32-bit int, long, pointer,
238 and off_t types.
239 _CS_XBS5_ILP32_OFF32_LIBS
242 If sysconf(_SC_XBS5_ILP32_OFF32) returns −1 the meaning of this
244 value is unspecified. Otherwise, this value is the set of
245 libraries to be given to the cc and c89 utilities to build an
246 application using a programming model with 32-bit int, long,
247 pointer, and off_t types.
248 _CS_XBS5_ILP32_OFF32_LINTFLAGS
251 If sysconf(_SC_XBS5_ILP32_OFF32) returns −1 the meaning of this
253 value is unspecified. Otherwise, this value is the set of options
254 to be given to the lint utility to check application source using a
255 programming model with 32-bit int, long, pointer, and off_t types.
256 _CS_XBS5_ILP32_OFFBIG_CFLAGS
259 If sysconf(_SC_XBS5_ILP32_OFFBIG) returns −1 the meaning of this
261 value is unspecified. Otherwise, this value is the set of initial
262 options to be given to the cc and c89 utilities to build an appli‐
263 cation using a programming model with 32-bit int, long, and pointer
264 types, and an off_t type using at least 64 bits.
265 _CS_XBS5_ILP32_OFFBIG_LDFLAGS
268 If sysconf(SC_XBS5_ILP32_OFFBIG) returns −1 the meaning of this
270 value is unspecified. Otherwise, this value is the set of final
271 options to be given to the cc and c89 utilities to build an appli‐
272 cation using a programming model with 32-bit int, long, and pointer
273 types, and an off_t type using at least 64 bits.
274 _CS_XBS5_ILP32_OFFBIG_LIBS
277 If sysconf(_SC_XBS5_ILP32_OFFBIG) returns −1 the meaning of this
279 value is unspecified. Otherwise, this value is the set of
280 libraries to be given to the cc and c89 utilities to build an
281 application using a programming model with 32-bit int, long, and
282 pointer types, and an off_t type using at least 64 bits.
283 _CS_XBS5_ILP32_OFFBIG_LINTFLAGS
286 If sysconf(_SC_XBS5_ILP32_OFFBIG) returns −1 the meaning of this
288 value is unspecified. Otherwise, this value is the set of options
289 to be given to the lint utility to check an application using a
290 programming model with 32-bit int, long, and pointer types, and an
291 off_t type using at least 64 bits.
292 The confstr() function supports the following values for name, defined
296 in <unistd.h>, for SPARC only:
297 _CS_XBS5_LP64_OFF64_CFLAGS
299 If sysconf(_SC_XBS5_LP64_OFF64) returns −1 the meaning of this
301 value is unspecified. Otherwise, this value is the set of initial
302 options to be given to the cc and c89 utilities to build an appli‐
303 cation using a programming model with 64-bit int, long, pointer,
304 and off_t types.
305 _CS_XBS5_LP64_OFF64_LDFLAGS
308 If sysconf(_SC_XBS5_LP64_OFF64) returns −1 the meaning of this
310 value is unspecified. Otherwise, this value is the set of final
311 options to be given to the cc and c89 utilities to build an appli‐
312 cation using a programming model with 64-bit int, long, pointer,
313 and off_t types.
314 _CS_XBS5_LP64_OFF64_LIBS
317 If sysconf(_SC_XBS5_LP64_OFF64) returns −1 the meaning of this
319 value is unspecified. Otherwise, this value is the set of
320 libraries to be given to the cc and c89 utilities to build an
321 application using a programming model with 64-bit int, long,
322 pointer, and off_t types.
323 _CS_XBS5_LP64_OFF64_LINTFLAGS
326 If sysconf(_SC_XBS5_LP64_OFF64) returns −1 the meaning of this
328 value is unspecified. Otherwise, this value is the set of options
329 to be given to the lint utility to check application source using a
330 programming model with 64-bit int, long, pointer, and off_t types.
331 _CS_XBS5_LPBIG_OFFBIG_CFLAGS
334 If sysconf(_SC_XBS5_LPBIG_OFFBIG) returns −1 the meaning of this
336 value is unspecified. Otherwise, this value is the set of initial
337 options to be given to the cc and c89 utilities to build an appli‐
338 cation using a programming model with an int type using at least 32
339 bits and long, pointer, and off_t types using at least 64 bits.
340 _CS_XBS5_LPBIG_OFFBIG_LDFLAGS
343 If sysconf(_SC_XBS5_LPBIG_OFFBIG) returns −1 the meaning of this
345 value is unspecified. Otherwise, this value is the set of final
346 options to be given to the cc and c89 utilities to build an appli‐
347 cation using a programming model with an int type using at least 32
348 bits and long, pointer, and off_t types using at least 64 bits.
349 _CS_XBS5_LPBIG_OFFBIG_LIBS
352 If sysconf(_SC_XBS5_LPBIG_OFFBIG) returns −1 the meaning of this
354 value is unspecified. Otherwise, this value is the set of
355 libraries to be given to the cc and c89 utilities to build an
356 application using a programming model with an int type using at
357 least 32 bits and long, pointer, and off_t types using at least 64
358 bits.
359 _CS_XBS5_LPBIG_OFFBIG_LINTFLAGS
362 If sysconf(_SC_XBS5_LPBIG_OFFBIG) returns −1 the meaning of this
364 value is unspecified. Otherwise, this value is the set of options
365 to be given to the lint utility to check application source using a
366 programming model with an int type using at least 32 bits and long,
367 pointer, and off_t types using at least 64 bits.
368
371 If name has a configuration-defined value, the confstr() function
372 returns the size of buffer that would be needed to hold the entire con‐
373 figuration-defined value. If this return value is greater than len,
374 the string returned in buf is truncated.
375 If name is invalid, confstr() returns 0 and sets errno to indicate the
378 error.
379 If name does not have a configuration-defined value, confstr() returns
382 0 and leaves errno unchanged.
383
385 The confstr() function will fail if:
386 EINVAL The value of the name argument is invalid.
388
391 See attributes(5) for descriptions of the following attributes:
392 ┌─────────────────────────────┬─────────────────────────────┐
397 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
398 ├─────────────────────────────┼─────────────────────────────┤
399 │Interface Stability │Standard │
400 ├─────────────────────────────┼─────────────────────────────┤
401 │MT-Level │Mt-Safe │
402 └─────────────────────────────┴─────────────────────────────┘
403
405 pathconf(2), sysconf(3C), attributes(5), lfcompile(5), lfcompile64(5),
406 standards(5)
407SunOS 5.11 15 Dec 2003 confstr(3C)