87 lines
2.4 KiB
C
87 lines
2.4 KiB
C
/*
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FUNCTION
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<<getenv>>---look up environment variable
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INDEX
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getenv
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INDEX
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environ
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SYNOPSIS
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#include <stdlib.h>
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char *getenv(const char *<[name]>);
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DESCRIPTION
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<<getenv>> searches the list of environment variable names and values
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(using the global pointer ``<<char **environ>>'') for a variable whose
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name matches the string at <[name]>. If a variable name matches,
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<<getenv>> returns a pointer to the associated value.
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RETURNS
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A pointer to the (string) value of the environment variable, or
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<<NULL>> if there is no such environment variable.
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PORTABILITY
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<<getenv>> is ANSI, but the rules for properly forming names of environment
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variables vary from one system to another.
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<<getenv>> requires a global pointer <<environ>>.
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*/
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/*
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* Copyright (c) 1987, 2000 Regents of the University of California.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that: (1) source distributions retain this entire copyright
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* notice and comment, and (2) distributions including binaries display
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* the following acknowledgement: ``This product includes software
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* developed by the University of California, Berkeley and its contributors''
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* in the documentation or other materials provided with the distribution
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* and in all advertising materials mentioning features or use of this
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* software. Neither the name of the University nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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#ifndef _REENT_ONLY
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#include <stdlib.h>
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#include <stddef.h>
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#include <string.h>
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/*
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* _findenv --
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* Returns pointer to value associated with name, if any, else NULL.
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* Sets offset to be the offset of the name/value combination in the
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* environmental array, for use by setenv(3) and unsetenv(3).
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* Explicitly removes '=' in argument name.
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*
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* This routine *should* be a static; don't use it.
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*/
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char *
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_findenv (register const char *name,
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int *offset)
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{
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return _findenv_r (_REENT, name, offset);
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}
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/*
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* getenv --
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* Returns ptr to value associated with name, if any, else NULL.
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*/
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char *
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getenv (const char *name)
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{
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int offset;
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return _findenv_r (_REENT, name, &offset);
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}
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#endif /* !_REENT_ONLY */
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