Copyright (c) 1997 Shigio Yamaguchi. All rights reserved.
Copyright (c) 1999 Tama Communications Corporation. All rights reserved.

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.Dd August 7, 2022 .Dt REL2ABS 3 .Os .Sh NAME .Nm rel2abs .Nd make an absolute path name from a relative path name .Sh SYNOPSIS .Ft "char *" .Fn rel2abs "const char *path" "const char *base" "char *result" "size_t size" .Sh DESCRIPTION The .Fn rel2abs function makes an absolute path name from a relative path name .Fa path based on a directory .Fa base and copies the resulting path name into the memory referenced by .Fa result . The .Fa result argument must refer to a buffer capable of storing at least .Fa size character The resulting path name may include symbolic links. .Fn abs2rel doesn't check whether or not any path exists. .Sh "RETURN VALUES" The .Fn rel2abs function returns absolute path name on success. If an error occurs, it returns .Dv NULL . .Sh EXAMPLES char result[MAXPATHLEN]; char *path = rel2abs("../../src/sys", "/usr/local/lib", result, MAXPATHLEN); yields: path == "/usr/src/sys" Similarly, path1 = rel2abs("src/sys", "/usr", result, MAXPATHLEN); path2 = rel2abs(".", "/usr/src/sys", result, MAXPATHLEN); yields: path1 == "/usr/src/sys" path2 == "/usr/src/sys" .Sh ERRORS The .Fn rel2abs function may fail and set the external variable .Va errno to indicate the error. l -tag -width Er t Bq Er EINVAL The .Fa base directory isn't an absolute path name or the .Fa size argument is zero. t Bq Er ERANGE The .Fa size argument is greater than zero but smaller than the length of the pathname plus 1 .Sh SEE ALSO .Xr abs2rel 3 .Sh AUTHORS .An Shigio Yamaguchi (shigio@tamacom.com)